Release Notes for the Catalyst 3750, 3560, 3560-C, 2960, 2960-S, 2960-C, and 2960-Plus Switches, Cisco IOS Release 15.0(2)SE and Later
Available Languages
Table of Contents
Device Manager System Requirements
Finding the Software Version and Feature Set
Upgrading a Switch by Using the Device Manager or Network Assistant
Upgrading a Switch by Using the CLI
Recovering from a Software Failure
New in Cisco IOS Release 15.0(2)SE5
New in Cisco IOS Release 15.0(2)SE3
New in Cisco IOS Release 15.0(2)SE1
New in Cisco IOS Release 15.0(2)SE
Minimum Cisco IOS Release for Major Features
Stacking (Catalyst 3750 or Cisco EtherSwitch service module switch stack only)
Catalyst 2960-S Control Plane Protection
Caveats Resolved in Cisco IOS Release 15.0(2)SE12
Caveats Resolved in Cisco IOS Release 15.0(2)SE11
Caveats Resolved in Cisco IOS Release 15.0(2)SE10a
Caveats Resolved in Cisco IOS Release 15.0(2)SE10
Caveats Resolved in Cisco IOS Release 15.0(2)SE9
Caveats Resolved in Cisco IOS Release 15.0(2)SE8
Caveats Resolved in Cisco IOS Release 15.0(2)SE7
Caveats Resolved in Cisco IOS Release 15.0(2)SE6
Caveats Resolved in Cisco IOS Release 15.0(2)SE5
Caveats Resolved in Cisco IOS Release 15.0(2)SE4
Caveats Resolved in Cisco IOS Release 15.0(2)SE3
Caveats Resolved in Cisco IOS Release 15.0(2)SE2
Caveats Resolved in Cisco IOS Release 15.0(2)SE1
Caveats Resolved in Cisco IOS Release 15.0(2)SE
Updates to the Catalyst 3560 and 2960 Software Configuration Guides
Information Added to the “Configuring Interface Characteristics” Chapter
Universal Power over Ethernet Support
Obtaining Documentation and Submitting a Service Request
Release Notes for the Catalyst 3750, 3560, 3560-C, 2960, 2960-S, 2960-C, and 2960-Plus Switches, Cisco IOS Release 15.0(2)SE and Later
Cisco IOS Release 15.0(2)SE and later runs on Catalyst 3750, 3560, 3560-C, 2960, 2960-S, 2960-C, and 2960-Plus switches and on Cisco EtherSwitch service modules.
Note Not all Catalyst 3750 and 3560 switches can run this release. These models are not supported in Cisco IOS Release 12.2(58)SE1 and later: WS-C3560-24TS, WS-C3560-24PS. WS-C3560-48PS, WS-C3560-48TS, WS-C3750-24PS, WS-C3750-24TS, WS-C3750-48PS, WS-C3750-48TS, WS-3750G-24T, WS-C3750G-12S, WS-C3750G-24TS, WS-C3750G-16TD. For ongoing maintenance rebuilds for these models, use Cisco IOS Release 12.2(55)SE and later (SE1, SE2, and so on).
The Catalyst 3750 switches and the Cisco EtherSwitch service modules support stacking through Cisco StackWise technology. The Catalyst 3560 and 2960 switches do not support switch stacking. Catalyst 2960-S does support stacking. Unless otherwise noted, the term switch refers to a standalone switch and to a switch stack.
The Catalyst 3560-C switch does not support the IP services image.
These release notes include important information about Cisco IOS Release 15.0(2)SE and any limitations, restrictions, and caveats that apply to the releases. Verify that these release notes are correct for your switch:
- If you are installing a new switch, see the Cisco IOS release label on the rear panel of your switch.
- If your switch is on, use the show version privileged EXEC command. See the “Finding the Software Version and Feature Set” section.
- If you are upgrading to a new release, see the software upgrade filename for the software version. See the “Deciding Which Files to Use” section.
You can download the switch software from this site (registered Cisco.com users with a login password):
http://www.cisco.com/cisco/web/download/index.htmlSystem Requirements
Supported Hardware
Table 1 Catalyst 3750 and Cisco EtherSwitch Service Modules Supported
24 10/100/1000 PoE1 ports, 2 SFP2 module slots, and an integrated wireless LAN controller supporting up to 25 access points.
Cisco IOS Release 12.2(25)FZ or Cisco IOS Release 12.2(35)SE
24 10/100/1000 PoE ports, 2 SFP module slots, and an integrated wireless LAN controller supporting up to 50 access points
Cisco IOS Release 12.2(25)FZ or Cisco IOS Release 12.2(35)SE
NME-16ES-1G3
16 10/100 ports, 1 10/100/1000 Ethernet port, no StackWise connector ports, single-wide
16 10/100 PoE ports, 1 10/100/1000 Ethernet port, no StackWise connector ports, single-wide
23 10/100 ports, 1 10/100/1000 PoE port, no StackWise connector ports, extended single-wide
23 10/100 PoE ports, 1 10/100/1000 PoE port, no StackWise connector ports, extended single-wide
24 10/100 PoE ports, 1 SFP module port, 2 StackWise connector ports, extended double-wide
48 10/100 PoE ports, 2 SFP module ports, no StackWise connector ports, extended double-wide
8 10/100 PoE ports and 1 dual-purpose port4 (one 10/100/1000BASE-T copper port and one SFP module slot)
12 Ethernet 10/100 ports with PoE and 1 dual-purpose 10/100/1000 or SFP uplink
Table 3 Catalyst 2960, 2960-S and 2960-Plus Switches Supported
48 10/100 PoE ports, 2 10/100/1000 ports, and 2 SFP module slots
24 10/100 PoE ports and 2 dual-purpose ports
(2 10/100/1000BASE-T copper ports and 2 SFP module slots)24 10/100 ports (8 of which are PoE) and 2 dual-purpose ports
(2 10/100/1000BASE-T copper ports and 2 SFP module slots)8 10/100 ports and 1 dual-purpose port3 (1 10/100/1000BASE-T copper port and1 SFP module slot)
48 10/100 PoE ports, 1 10/100/1000 ports and 2 SFP module slots
24 10/100BASE-T Ethernet ports and 2 dual-purpose ports (two 10/100/1000BASE-T copper ports and two SFP module slots)
48 10/100BASE-T Ethernet ports and 2 dual-purpose ports (two 10/100/1000BASE-T copper ports and two SFP module slots)
8 10/100 Ethernet ports and 1 dual-purpose port (one 10/100/1000BASE-T copper port and one SFP module slot)
7 10/100/1000 Ethernet ports and 1 dual-purpose port (one 10/100/1000BASE-T copper port and one SFP module slot)
24 10/100 ports, 8 of which are PoE, and 2 10/100/1000 ports
24 10/100 Power over Ethernet (PoE) ports and 2 dual-purpose ports (2 10/100/1000BASE-T copper ports and 2 small form-factor pluggable [SFP] module slots)
24 10/100BASE-T Ethernet ports and 2 10/100/1000BASE-T Ethernet ports
48 10/100BASE-T Ethernet ports 2 10/100/1000BASE-T Ethernet ports
24 10/100/1000BASE-T Ethernet ports, including 4 dual-purpose ports (four 10/100/1000BASE-T copper ports and four SFP module slots)
48 10/100/1000BASE-T Ethernet ports, including 4 dual-purpose ports (four 10/100/1000BASE-T copper ports and four SFP module slots)
Catalyst 2960S-48FPD-L5
48 10/100/1000 Power over Ethernet Plus (PoE+) ports (PoE budget of 740 W) and 2 SFP+6 module slots
Catalyst 2960S-48LPD-L 1
48 10/100/1000 PoE+ ports (PoE budget of 370 W) and 2 SFP+ module slots
Catalyst 2960S-24PD-L 1
24 10/100/1000 PoE+ ports (PoE budget of 370 W) and 2 SFP+ module slots
Catalyst 2960S-48TD-L 1
Catalyst 2960S-24TD-L 1
Catalyst 2960S-48FPS-L 1
48 10/100/1000 PoE+ ports (PoE budget of 740 W) and 4 SFP module slots
Catalyst 2960S-48LPS-L 1
48 10/100/1000 PoE+ ports (PoE budget of 370 W) and 4 SFP module slots
Catalyst 2960S-24PS-L 1
24 10/100/1000 PoE+ ports (PoE budget of 370 W) and 4 SFP module slots
Catalyst 2960S-48TS-L 1
Catalyst 2960S-24TS-L 1
Catalyst 2960S-F48FPS-L 1
48 10/100 PoE+ ports (PoE budget of 740 W) and 4 SFP module slots
Catalyst 2960S-F48LPS-L 1
48 10/100 PoE+ ports (PoE budget of 370 W) and 4 SFP module slots
Catalyst 2960S-F48TS-L 1
Catalyst 2960S-F24PS-L 1
24 10/100 PoE+ ports (PoE budget of 370 W) and 2 SFP module slots
Catalyst 2960S-F24TS-L 1
24 10/100BASE-TX ports (8 of which are PoE) and 2 dual-purpose ports
48 10/100B SE-TX PoE ports, 2 10/100/1000 ports, and 2 SFP module slots
24 10/100BASE-TX Ethernet ports and 2 dual-purpose ports (no RPS port)
48 10/100BASE-TX Ethernet ports and 2 dual-purpose ports (no RPS port)
48 10/100BASE-TX PoE ports, 2 10/100/1000BASE-T copper ports, and 2 SFP module slots
24 10/100BASE-TX ports (8 of which are PoE) and 2 dual-purpose ports
Cisco 2520 Connected Grid Switch (CGS 2520) is a rugged switch designed for the harsh, rugged environments often found in the energy and utility industries.
http://www.cisco.com/en/US/partner/products/ps10978/products_installation_and_configuration_guides_list.html
1000BASE-CWDM7, -LX, SX, -T, -ZX
100BASE-FX MMF8
Support for eight additional DWDM SFP optical modules. For a complete list of supported SFPs and part numbers, see the data sheet:
http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/product_data_sheet0900aecd80371991.html1000BASE-BX, -CWDM, -LX/LH, -SX, -ZX
For a complete list of supported SFPs and part numbers, see the compatibility information for SFP modules:
http://www.cisco.com/en/US/partner/products/hw/modules/ps5455/products_device_support_tables_list.htmlXENPAK modules9
Cisco RPS 675 Redundant Power System
Cisco RPS 300 Redundant Power System (supported only on the Catalyst 2960 switch)
Supported on all software releases
Software Requirements
- Windows 2000, XP, Vista, and Windows Server 2003.
- Internet Explorer 6.0 or 7.0, and Firefox up to version 27, with JavaScript enabled.
The device manager verifies the browser version when starting a session and does not require a plug-in.
Cluster Compatibility
You cannot create and manage switch clusters through the device manager. To create and manage switch clusters, use the command-line interface (CLI) or the Network Assistant application.
When creating a switch cluster or adding a switch to a cluster, follow these guidelines:
- When you create a switch cluster, we recommend configuring the highest-end switch in your cluster as the command switch.
- If you are managing the cluster through Network Assistant, the switch with the latest software should be the command switch.
- The standby command switch must be the same type as the command switch. For example, if the command switch is a Catalyst 3750 switch, all standby command switches must be Catalyst 3750 switches.
For additional information about clustering, see Getting Started with Cisco Network Assistant and Release Notes for Cisco Network Assistant (not orderable but available on Cisco.com), the software configuration guide, the command reference, and the Cisco EtherSwitch service module feature guide.
CNA Compatibility
Cisco IOS 12.2(50)SE and later is only compatible with Cisco Network Assistant (CNA) 5.0 and later. You can download Cisco Network Assistant from this URL:
http://www.cisco.com/pcgi-bin/tablebuild.pl/NetworkAssistantFor more information about Cisco Network Assistant, see the Release Notes for Cisco Network Assistant on Cisco.com.
Upgrading the Switch Software
- Finding the Software Version and Feature Set
- Deciding Which Files to Use
- Archiving Software Images
- Upgrading a Switch by Using the Device Manager or Network Assistant
- Upgrading a Switch by Using the CLI
- Recovering from a Software Failure
Finding the Software Version and Feature Set
The Cisco IOS image is stored as a bin file in a directory that is named with the Cisco IOS release. A subdirectory contains the files needed for web management. The image is stored on the system board flash device (flash:).
You can use the show version privileged EXEC command to see the software version that is running on your switch. The second line of the display shows the version.
Note For Catalyst 3750 and 3560 switches and the Cisco EtherSwitch service modules, although the show version output always shows the software image running on the switch, the model name shown at the end of this display is the factory configuration (IP base image or IP services image) and does not change if you upgrade the software image.
You can also use the dir filesystem : privileged EXEC command to see the directory names of other software images that you might have stored in flash memory.
Deciding Which Files to Use
The upgrade procedures in these release notes describe how to perform the upgrade by using a combined tar file. This file contains the Cisco IOS image file and the files needed for the embedded device manager. You must use the combined tar file to upgrade the switch through the device manager. To upgrade the switch through the command-line interface (CLI), use the tar file and the archive download-sw privileged EXEC command.
Catalyst 3750 IP base cryptographic image and device manager files. This image has the Kerberos, SSH12, Layer 2+, and basic Layer 3 routing features. This image also runs on the Cisco EtherSwitch service modules.
Catalyst 3750 IP services cryptographic image and device manager files. This image has the Kerberos, SSH, Layer 2+, and full Layer 3 features. This image also runs on the Cisco EtherSwitch service modules.
Catalyst 3560 IP base cryptographic image and device manager files. This image has the Kerberos, SSH, and Layer 2+, and basic Layer 3 routing features.
Catalyst 3560 IP services cryptographic image and device manager files. This image has the Kerberos, SSH, Layer 2+, and full Layer 3 features.
Catalyst 3560-C image with all supported universal image features and Web-based device manager, does not support MACsec encryption.
Catalyst 3560-C image with all supported universal image features and Web-based device manager.
Catalyst 3560 image with all supported universal image features and Web-based device manager, does not support MACsec encryption.
Catalyst 3560-C image with all supported universal image features and Web-based device manager.
Catalyst 2960 cryptographic image file and device manager files. This image has the Kerberos and SSH features.
Catalyst 2960 LAN Lite cryptographic image file and device manager files.
Catalyst 2960-C image with all supported universal image features and Web-based device manager.
Catalyst 2960-C image with all supported universal image features and Web-based device manager.
Catalyst 2960-SM LAN Base image with Web-based device manager.
Catalyst 2960-Plus cryptographic image file and device manager files. This image has the Kerberos and SSH features.
Catalyst 2960-Plus cryptographic image file and device manager files.
Archiving Software Images
Before upgrading your switch software, make sure that you have archived copies of the current Cisco IOS release and the Cisco IOS release to which you are upgrading. You should keep these archived images until you have upgraded all devices in the network to the new Cisco IOS image and until you have verified that the new Cisco IOS image works properly in your network.
Cisco routinely removes old Cisco IOS versions from Cisco.com. See Product Bulletin 2863 for more information:
http://www.cisco.com/en/US/prod/collateral/iosswrel/ps8802/ps6969/ps1835/
prod_bulletin0900aecd80281c0e.htmlYou can copy the bin software image file on the flash memory to the appropriate TFTP directory on a host by using the copy flash: tftp: privileged EXEC command.
Note Although you can copy any file on the flash memory to the TFTP server, it is time consuming to copy all of the HTML files in the tar file. We recommend that you download the tar file from Cisco.com and archive it on an internal host in your network.
You can also configure the switch as a TFTP server to copy files from one switch to another without using an external TFTP server by using the tftp-server global configuration command. For more information about the tftp-server command, see the “Basic File Transfer Services Commands” section of the Cisco IOS Configuration Fundamentals Command Reference, Release 12.2 :
http://www.cisco.com/en/US/docs/ios/fundamentals/command/reference/cf_t1.htmlUpgrading a Switch by Using the Device Manager or Network Assistant
You can upgrade switch software by using the device manager or Network Assistant. For detailed instructions, click Help .
Note When using the device manager to upgrade your switch, do not use or close your browser session after the upgrade process begins. Wait until after the upgrade process completes.
Upgrading a Switch by Using the CLI
This procedure is for copying the combined tar file to the switch. You copy the file to the switch from a TFTP server and extract the files. You can download an image file and replace or keep the current image.
To download software, follow these steps:
Step 1 Use Table 6 to identify the file that you want to download.
Step 2 Download the software image file:
a. If you are a registered customer, go to this URL and log in.
http://www.cisco.com/cisco/web/download/index.html
b. Navigate to Switches > LAN Switches - Access .
c. Navigate to your switch model.
d. Click IOS Software , then select the latest IOS release.
Download the image you identified in Step 1.
Caution If you are upgrading a Catalyst 3750 switch that is running a release earlier than Cisco IOS Release 12.1(19)EA1c, this release includes a bootloader upgrade. The bootloader can take up to 1 minute to upgrade the first time that the new software is loaded. Do not power cycle the switch during the bootloader upgrade.
Step 3 Copy the image to the appropriate TFTP directory on the workstation, and make sure that the TFTP server is properly configured.
For more information, see Appendix B in the software configuration guide for this release.
Step 4 Log into the switch through the console port or a Telnet session.
Step 5 (Optional) Ensure that you have IP connectivity to the TFTP server by entering this privileged EXEC command:
For more information about assigning an IP address and default gateway to the switch, see the software configuration guide for this release.
Step 6 Download the image file from the TFTP server to the switch. If you are installing the same version of software that is currently on the switch, overwrite the current image by entering this privileged EXEC command:
The /overwrite option overwrites the software image in flash memory with the downloaded one.
The /reload option reloads the system after downloading the image unless the configuration has been changed and not saved.
The / allow-feature-upgrade option allows installation of an image with a different feature set (for example, upgrade from the IP base image to the IP services image).
For // location , specify the IP address of the TFTP server.
For / directory / image-name .tar , specify the directory (optional) and the image to download. Directory and image names are case sensitive.
This example shows how to download an image from a TFTP server at 198.30.20.19 and to overwrite the image on the switch:
You can also download the image file from the TFTP server to the switch and keep the current image by replacing the /overwrite option with the /leave-old-sw option.
Installation Notes
Use these methods to assign IP information to your switch:
- The Express Setup program , as described in the switch getting started guide.
- The CLI-based setup program, as described in the switch hardware installation guide.
- The DHCP-based autoconfiguration, as described in the switch software configuration guide.
- Manually assigning an IP address, as described in the switch software configuration guide.
New Software Features
New in Cisco IOS Release 15.0(2)SE3
- IPv6 Router Advertisement (RA) Guard provides support for allowing the network administrator to block or reject unwanted or rogue RA Guards messages arriving at the network switch platform.
Note This feature is available in the LAN Base feature set.
New in Cisco IOS Release 15.0(2)SE1
- Cisco IOS Release 15.0(2)SE1 on the Catalyst 2960-S, 3750, 3560, 2960-C405, 2960-C405ex, 3560-C405, 3560-C405ex switches has been submitted for certification under FIPS 140-2 and Common Criteria compliance with the US Government, Security Requirements for Network Devices (pp_nd_v1.0), version 1.0, dated 10 December 2010.
Note The images for the Cisco IOS Release 15.0(2)SE1 on the Catalyst 2960-S, 3750, 3560, 2960-C405, 2960-C405ex, 3560-C405, 3560-C405ex switches are FIPS certified. For information about using FIPS certifies images, see the “Boot Loader Upgrade and Image Verification for the FIPS Mode of Operation” section in the “Assigning the Switch IP Address and Default Gateway” chapter of the software configuration guide.
FIPS 140-2 is a cryptographic-focused certification, required by many government and enterprise customers, which ensures the compliance of the encryption and decryption operations performed by the switch to the approved FIPS cryptographic strengths and management methods for safeguarding these operations. For more information, see:
– The security policy document at: http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/1401val2011.htm#1657
– The installation notes at: http://www.cisco.com/en/US/products/ps10745/prod_installation_guides_list.html
Common Criteria is an international standard (ISO/IEC 15408) for computer security certification. This standard is a set of requirements, tests, and evaluation methods that ensures that the Target of Evaluation complies with a specific Protection Profile or custom Security Target. For more information, see the security target document at:
http://www.niap-ccevs.org/st/vid10488/ .
- Support for Resilient Ethernet Protocol (REP). REP is a Cisco proprietary protocol that provides an alternative to Spanning Tree Protocol (STP) to control network loops, handle link failures, and improve convergence time in ring topologies. See the Configuring Resilient Ethernet Protocol chapter in the software configuration guide on cisco.com. (Catalyst 3560-CG and 3560-CPD switches)
New in Cisco IOS Release 15.0(2)SE
- Supports the Universal Power over Ethernet (UPoE) feature. Sources up to 60 W of power (2X 30W) over both signal and spare pairs of the RJ-45 Ethernet cable based on IEEE802.3at standards. Automatically detects UPoE-compliant power devices and negotiates power up to 60 W by using Layer 2 power negotiation protocols, such as CDP or LLDP. It also supplies 60 W power on ports without CDP/LLDP negotiations (for devices that do not support the required UPoE TLV). (Catalyst 2960-C and 3560- C switches)
For more information on UPoE, see Chapter 15, “Configuring Interface Characteristics” section “Univeral Power over Ethernet” on page 15- 13 of the software configuration guide on Cisco.com.
- Support for IOS IPv6 Host mode, which is compliant with the IPv6 Ready Logo Phase-2 Core Protocols test suite. (LAN Lite image for Catalyst 2960, 2960-C and 2960-S switches; IP Base image for Catalyst 3750, 3750v2, 3560, 3560v2 and 3650-C switches).
- Option to configure a default class on Catalyst 2960-S switches by using the class class-default policy-map configuration command. For more information, see the Configuring QoS chapter of the software configuration guide on Cisco.com. (Catalyst 2960-S switches)
- Support for OSPFv3 fast convergence. The OSPFv3 link-state advertisements (LSA) and shortest path first (SPF) throttling feature provides a dynamic method to slow down link-state advertisement updates in OSPFv3 during times of network instability. This feature also allows faster OSPFv3 convergence by providing LSA rate limiting in milliseconds. For more information, see the Configuring IPv6 Unicast Routing chapter of the software configuration guide on Cisco.com. (Catalyst 3750 and Catalyst 3560 switches)
- Change in the CLI option relating to OSPFv2 LSA rate limiting. The all keyword is now removed from the timers throttle lsa global configuration command. (Catalyst 3560-C, 3560v2, and 3750 v2 switches)
- Support for OSPFv3 authentication with IPsec. You can now use the IPsec secure socket API to authenticate OSPF for IPv6 (OSPFv3) packets to ensure that the packets are not altered and resent to the switch. For more information, see the Configuring IPv6 Unicast Routing chapter of the software configuration guide on Cisco.com. (Catalyst 3560, 3560-C, 3560v2, 3750, and 3750v2 switches)
- Support for first hop security (FHS) in IPv6. We support the following functions: IPv6 snooping, IPv6 FHS binding, neighbor discovery protocol (NDP) address gleaning, IPv6 data address gleaning, IPv6 dynamic host configuration protocol (DHCP) address gleaning, IPv6 device tracking, neighbor discovery (ND) Inspection, IPv6 port-based access list, IPv6 DHCP guard, IPv6 router advertisement (RA) guard, IPv6 source guard. For more information, see the Configuring IPv6 Host Functions chapter of the software configuration guide on Cisco.com. (Catalyst 2960-C, 2960-S and 3560-C switches)
- Support for specifying the VLAN to be used for Smart Install Management. The vstack startup-vlan command has been added. For more information, see the command reference on Cisco.com.
- Support for configurable MAC authentication bypass (MAB). You can configure how MAB authentication is performed for client MAC address that deviate from the expected standard format or where the RADIUS configuration requires that the user name and password to differ. For more information, see the Configuring IEEE 802.1x Port-Based Authentication chapter in the software configuration guide on Cisco.com.
- Support for negotiating universal PoE (UPoE). For more information, see Updates to the Catalyst 3560 and 2960 Software Configuration Guides. (Catalyst 2960-C and 3560-C switches)
- Support for Media Access Control Security (MACsec). The switch supports 802.1AE encryption with MACsec Key Agreement (MKA) on downlink and uplink ports for encryption between the switch and host devices. For more information, see the Configuring MACsec Encryption chapter in the software configuration guide. (Catalyst 3560-C)
- Support for IKEv2 and IPSecv3 protocols. (IP Base image for Catalyst 3750, 3750v2, 3560, 3560v2 switches)
- Support for Port ACLs on the Layer 2 interface of a switch. (LAN Base image for Catalyst 2960-C and 2960-S switches; IP Base image for Catalyst 3560-C switch)
- Support for Router ACLs on switch virtual interfaces (SVIs). The SVIs may be Layer 3 interfaces to VLANs, physical Layer 3 interfaces, or Layer 3 EtherChannel interfaces. (LAN Base image for Catalyst 2960-C and 2960-S switches; IP Base image for Catalyst 3560-C switch)
- Support for configuring static IPv6 routes in the routing table so that packet data can be sent to networks that are not directly connected to the router. (LAN Base image for Catalys t 2960, 2960-C and 2960-S switches)
- Support for Cisco TrustSec SXP version 2, syslog messages, and SNMP support is now extended to the LAN Base license. (IP Base image for Catalyst 3560-C switch)
- Support for port security on Etherchannels. For more information, see the Configuring Port-Based Traffic Control chapter in the software configuration guide.
- Support for IP Source Guard on Etherchannels. For more information, see the Configuring DHCP and IP Source Guard chapter in the software configuration guide.
- Support for Precision Time Protocol (PTP) and Temperature and Voltage Monitoring on the Cisco CGS 2520 Switch.
Minimum Cisco IOS Release for Major Features
Table 7 lists the minimum software release required to support the major features of the Catalyst 3750, 3560, 2960-S, and 2960 switches and the Cisco EtherSwitch service modules.
Limitations and Restrictions
You should review this section before you begin working with the switch. These are known limitations that will not be fixed, and there is not always a workaround. Some features might not work as documented, and some features could be affected by recent changes to the switch hardware or software.
Cisco IOS Limitations
Unless otherwise noted, these limitations apply to the Catalyst 3750, and 3560, and 2960 switches and the Cisco EtherSwitch service modules:
Configuration
This problem occurs under these conditions:
– When the switch is booted up without a configuration (no config.text file in flash memory).
– When the switch is connected to a DHCP server that is configured to give an address to it (the dynamic IP address is assigned to VLAN 1).
– When an IP address is configured on VLAN 1 before the dynamic address lease assigned to VLAN 1 expires.
The workaround is to reconfigure the static IP address. (CSCea71176 and CSCdz11708)
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) When the show interface privileged EXEC is entered on a port that is running IEEE 802.1Q, inconsistent statistics from ports running IEEE 802.1Q might be reported.
The workaround is to upgrade to Cisco IOS Release 12.1(20)EA1. (CSCec35100)
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) When you change a port from a nonrouted port to a routed port or the reverse, the applied auto-QoS setting is not changed or updated when you verify it by using the show running interface or show mls qos interface user EXEC commands.
1. Disable auto-QoS on the interface.
2. Change the routed port to a nonrouted port or the reverse.
3. Re-enable auto-QoS on the interface. (CSCec44169)
- When connected to some third-party devices that send early preambles, a switch port operating at 100 Mb/s full duplex or 100 Mb/s half duplex might bounce the line protocol up and down. The problem is observed only when the switch is receiving frames.
The workaround is to configure the port for 10 Mb/s and half duplex or to connect a hub or a nonaffected device to the switch. (CSCed39091)
- The DHCP snooping binding database is not written to flash memory or a remote file in any of these situations:
– (Catalyst 3750 switch and Cisco EtherSwitch service modules) When the Network Time Protocol (NTP) is configured, but the NTP clock is not synchronized. You can check the clock status by entering the show NTP status privileged EXEC command and verifying that the network connection to the NTP server and the peer work correctly.
– (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) The DHCP snooping database file is manually removed from the file system. After enabling the DHCP snooping database by configuring a database URL, a database file is created. If the file is manually removed from the file system, the DHCP snooping database does not create another database file. You need to disable the DHCP snooping database and enable it again to create the database file.
– (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) The URL for the configured DHCP snooping database was replaced because the original URL was not accessible. The new URL might not take effect after the timeout of the old URL.
No workaround is necessary; these are the designed behaviors. (CSCed50819)
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) When dynamic ARP inspection is enabled on a switch or switch stack, ARP and RARP packets greater than 2016 bytes are dropped by the switch or switch stack. This is a hardware limitation.
However, when dynamic ARP inspection is not enabled and a jumbo MTU is configured, ARP and RARP packets are correctly bridged in hardware. (CSCed79734)
- (Catalyst 3750 switches and Cisco EtherSwitch service modules) Dynamic ARP inspection log entries might be lost after a switch failure. Any log entries that are still in the log buffer (have not been output as a system message) on a switch that fails are lost.
When you enter the show ip arp inspection log privileged EXEC command, the log entries from all switches in the stack are moved to the switch on which you entered the command.
There is no workaround. (CSCed95822)
- When port security is enabled on an interface in restricted mode and the switchport block unicast interface command has been entered on that interface, MAC addresses are incorrectly forwarded when they should be blocked
The workaround is to enter the no switchport block unicast interface configuration command on that specific interface. (CSCee93822)
There is no workaround. This is a cosmetic error and does not affect the functionality of the switch. (CSCef59331)
- (Cisco EtherSwitch service modules) You cannot change the console baud rate by using the switch CLI. The console on the Cisco EtherSwitch service modules only supports three baud rates (9600 b/s, 19200 b/s, and 38400 b/s) and must be set at the bootloader prompt. The switch rejects a CLI command to change the baud rate.
To change the baud rate, reload the Cisco EtherSwitch service module with the bootloader prompt. You can then change the baud rate and change the speed on the TTY line of the router connected to the Cisco EtherSwitch Service module console.
There is no workaround. (CSCeh50152)
- The switch might display tracebacks similar to this example when an EtherChannel interface port-channel type changes from Layer 2 to Layer 3 or the reverse:
15:50:11: %COMMON_FIB-4-FIBNULLHWIDB: Missing hwidb for fibhwidb Port-channel1 (ifindex 1632) -Traceback= A585C B881B8 B891CC 2F4F70 5550E8 564EAC 851338 84AF0C 4CEB50 859DF4 A7BF28 A98260 882658 879A58(CSCsh12472 [Catalyst 3750 and 3560 switches])
The workaround is to configure aggressive UDLD. (CSCsh70244).
- A ciscoFlashMIBTrap message appears during switch startup. This does not affect switch functionality. (CSCsj46992)
- When you enter the boot host retry timeout global configuration command to specify the amount of time that the client should keep trying to download the configuration and you do not enter a timeout value, the default value is zero, which should mean that the client keeps trying indefinitely. However, the client does not keep trying to download the configuration.
The workaround is to always enter a non zero value for the timeout value when you enter the boot host retry timeout timeout-value command. (CSCsk65142)
- When the configuration file is removed from the switch and the switch is rebooted, port status for VLAN 1 and the management port (Fast Ethernet 0) is sometimes reported as
upand sometimes asdown, resulting in conflicts. This status depends on when you respond to the reboot query:
Would you like to enter the initial configuration dialog?– After a reboot if you wait until the Line Protocol status of VLAN 1 appears on the console before responding, VLAN 1 line status is always shown as
down. This is the correct state.– The problem (VLAN 1 reporting
up) occurs if you respond to the query before VLAN 1 line status appears on the console.The workaround is to wait for approximately 1 minute after rebooting and until the VLAN 1 interface line status appears on the console before you respond to the query. (CSCsl02680) (Catalyst 3750 and 3560 switches)
– Two-link ports on the same switch are connected with a crossover cable.
– The switch is running Cisco IOS 12.2(50)SE3 or later.
The workaround is to connect the two ports with a straight-through cable. (CSCsr41271) (Catalyst 3750V2 and Catalyst 3560V2 PoE switches and Cisco Etherswitch service modules only)
- If you enter the show tech-support privileged EXEC command after you enter the remote command { all | stack-member-number } privileged EXEC command, the complete output does not appear.
The workaround is to use the session stack-member-number privileged EXEC command. (CSCsz38090)
- When authorization and accounting are enabled on the switch and you use the interface range command to change the configuration on a range of interfaces, the change might cause high CPU utilization and authentication failures.
The workaround is to disable authorization and accounting or to enter the configuration change for one interface at a time. (CSCsg80238, CSCti76748)
Ethernet
- (Cisco EtherSwitch service modules) Link connectivity might be lost between some older models of the Intel Pro1000 NIC and the 10/100/1000 switch port interfaces. The loss of connectivity occurs between the NIC and Gigabit Ethernet ports on the Cisco EtherSwitch service modules
– Contact the NIC vendor, and get the latest driver for the card.
– Configure the interface for 1000 Mb/s instead of for 10/100 Mb/s.
– Connect the NIC to an interface that is not listed here. (CSCea77032)
For more information, enter CSCea77032 in the Cisco Bug Search Tool .
- (Cisco EtherSwitch service modules) When a Cisco EtherSwitch service module reloads or the internal link resets, there can be up to a 45-second delay in providing power to PoE devices, depending on the configuration. If the internal Gigabit Ethernet interface on a Cisco EtherSwitch service module connected to the router is configured as a switch port in access mode or in trunk mode, the internal link is not operational until it reaches the STP forwarding state. Therefore, the PoE that comes from the host router is also not available until the internal Gigabit Ethernet link reaches the STP forwarding state. This is due to STP convergence time. This problem does not occur on routed ports.
If the Cisco EtherSwitch service module is in access mode, the workaround is to enter the spanning-tree portfast interface configuration command on the internal Gigabit Ethernet interface. If the service module is in trunk mode, there is no workaround.
- Traffic on EtherChannel ports is not perfectly load-balanced. Egress traffic on EtherChannel ports are distributed to member ports on load balance configuration and traffic characteristics like MAC or IP address. More than one traffic stream may map to same member ports based on hashing results calculated by the ASIC.
If this happens, uneven traffic distribution will happen on EtherChannel ports.
Changing the load balance distribution method or changing the number of ports in the EtherChannel can resolve this problem. Use any of these workarounds to improve EtherChannel load balancing:
– for random source-ip and dest-ip traffic, configure load balance method as src-dst-ip
– for incrementing source-ip traffic, configure load balance method as src-ip
– for incrementing dest-ip traffic, configure load balance method as dst-ip
– Configure the number of ports in the EtherChannel so that the number is equal to a power of 2 (i.e. 2, 4, or 8)
For example, with load balance configured as dst-ip with 150 distinct incrementing destination IP addresses, and the number of ports in the EtherChannel set to either 2, 4, or 8, load distribution is optimal.(CSCeh81991)
EtherSwitch Modules
Fallback Bridging
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) If a bridge group contains a VLAN to which a static MAC address is configured, all non-IP traffic in the bridge group with this MAC address destination is sent to all ports in the bridge group.
The workaround is to remove the VLAN from the bridge group or to remove the static MAC address from the VLAN. (CSCdw81955)
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) Known unicast (secured) addresses are flooded within a bridge group if secure addresses are learned or configured on a port and the VLAN on this port is part of a bridge group. Non-IP traffic destined to the secure addresses is flooded within the bridge group.
The workaround is to disable fallback bridging or to disable port security on all ports in all VLANs participating in fallback bridging. To remove an interface from a bridge group and to remove the bridge group, use the no bridge-group bridge-group interface configuration command. To disable port security on all ports in all VLANs participating in fallback bridging, use the no switchport port-security interface configuration command. (CSCdz80499)
HSRP
- When the active switch fails in a switch cluster that uses HSRP redundancy, the new active switch might not contain a full cluster member list.
The workaround is to ensure that the ports on the standby cluster members are not in the spanning-tree blocking state. To verify that these ports are not in the blocking state, see the “Configuring STP” chapter in the software configuration guide. (CSCec76893)
IP
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) The switch does not create an adjacent table entry when the ARP timeout value is 15 seconds and the ARP request times out.
The workaround is to not set an ARP timeout value lower than 120 seconds. (CSCea21674)
- When the rate of received DHCP requests exceeds 2,000 packets per minute for a long time, the response time might be slow when you are using the console.
The workaround is to use rate limiting on DHCP traffic to prevent a denial of service attack from occurring. (CSCeb59166)
IP Telephony
- After you change the access VLAN on a port that has IEEE 802.1x enabled, the IP phone address is removed. Because learning is restricted on IEEE 802.1x-capable ports, it takes approximately 30 seconds before the address is relearned.
No workaround is necessary. (CSCea85312)
- (Catalyst 3750 or 3560 PoE-capable switches and Cisco EtherSwitch service modules) The switch uses the IEEE classification to learn the maximum power consumption of a powered device before powering it. The switch grants power only when the maximum wattage configured on the port is less than or equal to the IEEE class maximum. This ensures that the switch power budget is not oversubscribed. There is no such mechanism in Cisco prestandard powered devices.
The workaround for networks with pre-standard powered devices is to leave the maximum wattage set at the default value (15.4 W). You can also configure the maximum wattage for the port for no less than the value the powered device reports as the power consumption through CDP messages. For networks with IEEE Class 0, 3, or 4 devices, do not configure the maximum wattage for the port at less than the default 15.4 W (15,400 milliwatts). (CSCee80668)
- Phone detection events that are generated by many IEEE phones connected to the switch ports can consume a significant amount of CPU time if the switch ports cannot power the phones because the internal link is down.
The workaround is to enter the power inline never interface configuration command on all the Fast Ethernet ports that are not powered by but are connected to IP phones if the problem persists. (CSCef84975, Cisco EtherSwitch service modules only)
- Some access point devices are incorrectly discovered as IEEE 802.3af Class 1 devices. These access points should be discovered as Cisco pre-standard devices. The show power inline user EXEC command shows the access point as an IEEE Class 1 device.
The workaround is to power the access point by using an AC wall adaptor. (CSCin69533)
The workaround is to enable PoE and to configure the switch to recover from the PoE error-disabled state. (CSCsf32300)
Multicasting
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) The switch does not support tunnel interfaces for unicast routed traffic. Only Distance Vector Multicast Routing Protocol (DVMRP) tunnel interfaces are supported for multicast routing.
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) Nonreverse-path forwarded (RPF) IP multicast traffic to a group that is bridged in a VLAN is leaked onto a trunk port in the VLAN even if the port is not a member of the group in the VLAN, but it is a member of the group in another VLAN. Because unnecessary traffic is sent on the trunk port, it reduces the bandwidth of the port.
There is no workaround for this problem because non-RPF traffic is continuous in certain topologies. As long as the trunk port is a member of the group in at least one VLAN, this problem occurs for the non-RPF traffic. (CSCdu25219)
- If the number of multicast routes and Internet Group Management Protocol (IGMP) groups are more than the maximum number specified by the show sdm prefer global configuration command, the traffic received on unknown groups is flooded in the received VLAN even though the show ip igmp snooping multicast-table privileged EXEC command output shows otherwise.
The workaround is to reduce the number of multicast routes and IGMP snooping groups to less than the maximum supported value. (CSCdy09008)
- IGMP filtering is applied to packets that are forwarded through hardware. It is not applied to packets that are forwarded through software. Hence, with multicast routing enabled, the first few packets are sent from a port even when IGMP filtering is set to deny those groups on that port.
There is no workaround. (CSCdy82818)
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) When you use the ip access-group interface configuration command with a router access control list (ACL) to deny access to a group in a VLAN, multicast data to the group that is received in the VLAN is always flooded in the VLAN, regardless of IGMP group membership in the VLAN. This provides reachability to directly connected clients, if any, in the VLAN.
The workaround is to not apply a router ACL set to deny access to a VLAN interface. Apply the security through other means; for example, apply VLAN maps to the VLAN instead of using a router ACL for the group. (CSCdz86110)
- (Catalyst 3750 switch stack) If the stack master is power cycled immediately after you enter the ip mroute global configuration command, there is a slight chance that this configuration change might be lost after the stack master changes. This occurs because the stack master did not have time to propagate the running configuration to all the stack members before it was powered down. This problem might also affect other configuration commands.
There is no workaround. (CSCea71255)
- (Catalyst 3750 switches and Cisco EtherSwitch service modules) When you enable IP Protocol-Independent Multicast (PIM) on a tunnel interface, the switch incorrectly displays the
Multicast is not supported on tunnel interfaceserror message. IP PIM is not supported on tunnel interfaces.There is no workaround. (CSCeb75366)
- If an IGMP report packet has two multicast group records, the switch removes or adds interfaces depending on the order of the records in the packet:
– If the ALLOW_NEW_SOURCE record is before the BLOCK_OLD_SOURCE record, the switch removes the port from the group.
– If the BLOCK_OLD_SOURCE record is before the ALLOW_NEW_SOURCE record, the switch adds the port to the group.
There is no workaround. (CSCec20128)
- When IGMP snooping is disabled and you enter the switchport block multicast interface configuration command, IP multicast traffic is not blocked.
The switchport block multicast interface configuration command is only applicable to non-IP multicast traffic.
There is no workaround. (CSCee16865)
– You disable IP multicast routing or re-enable it globally on an interface.
– A switch mroute table temporarily runs out of resources and recovers later.
The workaround is to enter the clear ip mroute privileged EXEC command on the interface. (CSCef42436)
After you configure a switch to join a multicast group by entering the ip igmp join-group group-address interface configuration command, the switch does not receive join packets from the client, and the switch port connected to the client is removed from the IGMP snooping forwarding table.
– Cancel membership in the multicast group by using the no ip igmp join-group group-address interface configuration command on an SVI.
– Disable IGMP snooping on the VLAN interface by using the no ip igmp snooping vlan vlan-id global configuration command. (CSCeh90425)
Power
- Non-PoE devices attached to a network might be erroneously detected as an IEEE 802.3af- compliant powered device and powered by the Cisco EtherSwitch service module.
There is no workaround. You should use the power inline never interface configuration command on Cisco EtherSwitch service module ports that are not connected to PoE devices. (CSCee71979)
- When you enter the show power inline privileged EXEC command, the out put shows the total power used by all Cisco EtherSwitch service modules in the router. The remaining power shown is available for allocation to switching ports on all Cisco EtherSwitch service modules in the router.
To display the total power used by a specific EtherSwitch service module, enter the show power inline command on the router. This output appears:
This is not a problem because the display correctly shows the total used power and the remaining power available on the system. (CSCeg74337)
- Entering the shutdown and the no shutdown interface configuration commands on the internal link can disrupt the PoE operation. If a new IP phone is added while the internal link is in shutdown state, the IP phone does not get inline power if the internal link is brought up within 5 minutes.
The workaround is to enter the shutdown and the no shutdown interface configuration commands on the Fast Ethernet interface of a new IP phone that is attached to the service module port after the internal link is brought up. (CSCeh45465)
QoS
- Some switch queues are disabled if the buffer size or threshold level is set too low with the mls qos queue-set output global configuration command. The ratio of buffer size to threshold level should be greater than 10 to avoid disabling the queue.
The workaround is to choose compatible buffer sizes and threshold levels. (CSCea76893)
- When auto-QoS is enabled on the switch, priority queuing is not enabled. Instead, the switch uses shaped round robin (SRR) as the queuing mechanism. The auto-QoS feature is designed on each platform based on the feature set and hardware limitations, and the queuing mechanism supported on each platform might be different. There is no workaround. (CSCee22591)
- If you configure a large number of input interface VLANs in a class map, a traceback message similar to this might appear:
Routing
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) The switch does not support tunnel interfaces for unicast routed traffic. Only Distance Vector Multicast Routing Protocol (DVMRP) tunnel interfaces are supported for multicast routing.
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) A route map that has an ACL with a Differentiated Services Code Point (DSCP) clause cannot be applied to a Layer 3 interface. The switch rejects this configuration and displays a message that the route map is unsupported.
There is no workaround. (CSCea52915)
- On a Catalyst 3750 or a Cisco EtherSwitch service module switch stack with a large number of switched virtual interfaces (SVIs), routes, or both on a fully populated nine-member switch stack, this message might appear when you reload the switch stack or add a switch to the stack:
This error message means there is a temporary memory shortage that normally recovers by itself. You can verify that the switch stack has recovered by entering the show cef line user EXEC command and verifying that the line card states are
upandsync.No workaround is required because the problem is self-correcting. (CSCea71611)
- (Catalyst 3750 switches and Cisco EtherSwitch service modules) A spanning-tree loop might occur if all of these conditions are true:
– Port security is enabled with the violation mode set to protected.
– The maximum number of secure addresses is less than the number of switches connected to the port.
– There is a physical loop in the network through a switch whose MAC address has not been secured, and its BPDUs cause a secure violation.
The workaround is to change any one of the listed conditions. (CSCed53633)
Smart Install
- When upgrading switches in a stack, the director cannot send the correct image and configuration to the stack if all switches in the stack do not start at the same time. A switch in the stack could then receive an incorrect image or configuration.
The workaround is to use an on-demand upgrade to upgrade switches in a stack by entering the vstack download config and vstack download image commands. (CSCta64962)
- When you upgrade a Smart Install director to Cisco IOS Release 12.2(55)SE but do not upgrade the director configuration, the director cannot upgrade client switches.
When you upgrade the director to Cisco IOS Release 12.2(55)SE, the workaround is to also modify the configuration to include all built-in, custom, and default groups. You should also configure the tar image name instead of the image-list file name in the stored images. (CSCte07949)
- Backing up a Smart Install configuration could fail if the backup repository is a Windows server and the backup file already exists in the server.
The workaround is to use the TFTP utility of another server instead of a Windows server or to manually delete the existing backup file before backing up again. (CSCte53737)
- In a Smart Install network, when the director is connected between the client and the DHCP server and the server has options configured for image and configuration, then the client does not receive the image and configuration files sent by the DHCP server during an automatic upgrade. Instead the files are overwritten by the director and the client receives the image and configuration that the director sends.
– If client needs to upgrade using an image and configuration file configured in the DHCP server options, you should remove the client from the Smart Install network during the upgrade.
– In a network using Smart Install, you should not configure options for image and configuration in the DHCP server. For clients to upgrade using Smart Install, you should configure product-id specific image and configuration files in the director. (CSCte99366)
- In a Smart Install network with the backup feature enabled (the default), the director sends the backup configuration file to the client during zero-touch replacement. However, when the client is a switch in a stack, the client receives the seed file from the director instead of receiving the backup configuration file.
The workaround, if you need to configure a switch in a stack with the backup configuration, is to use the vstack download config privileged EXEC command so that the director performs an on-demand upgrade on the client.
– When the backup configuration is stored in a remote repository, enter the location of the repository.
– When the backup file is stored in the director flash memory, you must manually set the permissions for the file before you enter the vstack download config command. (CSCtf18775)
- If the director in the Smart Install network is located between an access point and the DHCP server, the access point tries to use the Smart Install feature to upgrade even though access points are not supported devices. The upgrade fails because the director does not have an image and configuration file for the access point.
There is no workaround. (CSCtg98656)
- When a Smart Install director is upgrading a client switch that is not Smart Install-capable (that is, not running Cisco IOS Release 12.2(52)SE or later), the director must enter the password configured on the client switch. If the client switch does not have a configured password, there are unexpected results depending on the software release running on the client:
– When you select the NONE option in the director CLI, the upgrade should be allowed and is successful on client switches running Cisco IOS Release 12.2(25)SE through 12.2(46)SE, but fails on clients running Cisco IOS Release 12.2(50)SE through 12.2(50)SEx.
– When you enter any password in the director CLI, the upgrade should not be allowed, but it is successful on client switches running Cisco IOS Release 12.2(25)SE through 12.2(46)SE, but fails on clients running Cisco IOS Release 12.2(50)SE through 12.2(50)SEx.
SPAN and RSPAN
- When the RSPAN feature is configured on a switch, Cisco Discovery Protocol (CDP) packets received from the RSPAN source ports are tagged with the RSPAN VLAN ID and forwarded to trunk ports carrying the RSPAN VLAN. When this happens a switch that is more than one hop away incorrectly lists the switch that is connected to the RSPAN source port as a CDP neighbor.
This is a hardware limitation. The workaround is to disable CDP on all interfaces carrying the RSPAN VLAN on the device connected to the switch. (CSCeb32326)
- (Cisco EtherSwitch service modules) An egress SPAN copy of routed unicast traffic might show an incorrect destination MAC address on both local and remote SPAN sessions. This limitation does not apply to bridged packets. The workaround for local SPAN is to use the replicate option. For a remote SPAN session, there is no workaround.
This is a hardware limitation and only applies to Cisco EtherSwitch service modules (CSCdy72835):
- (Cisco EtherSwitch service modules) Egress SPAN routed packets (both unicast and multicast) show the incorrect source MAC address. For remote SPAN packets, the source MAC address should be the MAC address of the egress VLAN, but instead the packet shows the MAC address of the RSPAN VLAN. For local SPAN packets with native encapsulation on the destination port, the packet shows the MAC address of VLAN 1. This problem does not appear with local SPAN when the encapsulation replicate option is used. This limitation does not apply to bridged packets. The workaround is to use the encapsulate replicate keywords in the monitor session global configuration command. Otherwise, there is no workaround.
This is a hardware limitation and only applies to Cisco EtherSwitch service modules (CSCdy81521):
- (Cisco EtherSwitch service modules) During periods of very high traffic when two RSPAN source sessions are configured, the VLAN ID of packets in one RSPAN session might overwrite the VLAN ID of the other RSPAN session. If this occurs, packets intended for one RSPAN VLAN are incorrectly sent to the other RSPAN VLAN. This problem does not affect RSPAN destination sessions. The workaround is to configure only one RSPAN source session.
This is a hardware limitation and only applies to Cisco EtherSwitch service modules (CSCea72326):
- (Catalyst 3750 or 3560 switches and Cisco EtherSwitch service modules) The egress SPAN data rate might degrade when fallback bridging or multicast routing is enabled. The amount of degradation depends on the processor loading. Typically, the switch can egress SPAN at up to 40,000 packets per second (64-byte packets). As long as the total traffic being monitored is below this limit, there is no degradation. However, if the traffic being monitored exceeds the limit, only a portion of the source stream is spanned. When this occurs, the following console message appears:
Decreased egress SPAN rate. In all cases, normal traffic is not affected; the degradation limits only how much of the original source stream can be egress spanned. If fallback bridging and multicast routing are disabled, egress SPAN is not degraded.There is no workaround. If possible, disable fallback bridging and multicast routing. If possible, use ingress SPAN to observe the same traffic. (CSCeb01216)
- On Catalyst 3750 switches, Catalyst 3560 switches, or on Cisco EtherSwitch service modules, some IGMP report and query packets with IP options might not be ingress-spanned. Packets that are susceptible to this problem are IGMP packets containing 4 bytes of IP options (IP header length of 24). An example of such packets would be IGMP reports and queries having the router alert IP option. Ingress-spanning of such packets is not accurate and can vary with the traffic rate. Typically, very few or none of these packets are spanned.
There is no workaround. (CSCeb23352)
- CDP, VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP) packets received from a SPAN source are not sent to the destination interfaces of a local SPAN session. The workaround is to use the monitor session session_number destination { interface interface-id encapsulation replicate} global configuration command for local SPAN. (CSCed24036)
Spanning Tree Protocol
When a switch or switch stack running Multiple Spanning Tree (MST) is connected to a switch running Rapid Spanning Tree Protocol (RSTP), the MST switch acts as the root bridge and runs per-VLAN spanning tree (PVST) simulation mode on boundary ports connected to the RST switch. If the allowed VLAN on all trunk ports connecting these switches is changed to a VLAN other than VLAN 1 and the root port of the RSTP switch is shut down and then enabled, the boundary ports connected to the root port move immediately to the forward state without going through the PVST+ slow transition.
Stacking (Catalyst 3750 or Cisco EtherSwitch service module switch stack only)
- If the stack master is immediately reloaded after adding multiple VLANs, the new stack master might fail. The workaround is to wait a few minutes after adding VLANs before reloading the stack master. (CSCea26207)
- If the console speed is changed on a stack, the configuration file is updated, but the baud rate is not. When the switch is reloaded, meaningless characters might appear on the console during bootup before the configuration file is parsed and the console speed is set to the correct value. If manual bootup is enabled or the startup configuration is deleted after you change the console speed, you cannot access the console after the switch reboots.
There is no workaround. (CSCec36644)
- If a switch is forwarding traffic from a Gigabit ingress interface to a 100 Mb/s egress interface, the ingress interface might drop more packets due to oversubscription if the egress interface is on a Fast Ethernet switch than if it is on a Gigabit Ethernet switch.
There is no workaround. (CSCed00328)
- If a stack member is removed from a stack and either the configuration is not saved or another switch is added to the stack at the same time, the configuration of the first member switch might be lost.
The workaround is to save the stack configuration before removing or replacing any switch in the stack. (CSCed15939)
- When the switchport and no switchport interface configuration commands are entered more than 20,000 times on a port of a Catalyst 3750 switch or on a Cisco EtherSwitch service module, all available memory is used, and the switch halts.
There is no workaround. (CSCed54150)
- In a private-VLAN domain, only the default private-VLAN IP gateways have sticky ARP enabled. The intermediate Layer 2 switches that have private VLAN enabled disable sticky ARP. When a stack master re-election occurs on one of the Catalyst 3750 or Cisco EtherSwitch service module default IP gateways, the message
IP-3-STCKYARPOVRappears on the consoles of other default IP gateways. Because sticky ARP is not disabled, the MAC address update caused by the stack master re-election cannot complete.The workaround is to complete the MAC address update by entering the clear arp privileged EXEC command. (CSCed62409)
- When a Catalyst 3750 switch or Cisco EtherSwitch service module is being reloaded in a switch stack, packet loss might occur for up to 1 minute while the Cisco Express Forwarding (CEF) table is downloaded to the switch. This only impacts traffic that will be routed through the switch that is being reloaded.
There is no workaround. (CSCed70894)
- Inconsistent private-VLAN configuration can occur on a switch stack if a new stack master is running the IP base image and the old stack master was running the IP services image.
Private VLAN is enabled or disabled on a switch stack, depending on whether or not the stack master is running the IP services image or the IP base image:
– If the stack master is running the IP services image, all stack members have private VLAN enabled.
– If the stack master is running the IP base image, all stack members have private VLAN disabled.
This occurs after a stack master re-election when the previous stack master was running the IP services image and the new stack master is running the IP base image. The stack members are configured with private VLAN, but any new switch that joins the stack will have private VLAN disabled.
These are the workarounds. Only one of these is necessary:
– Reload the stack after an IP services image to IP base image master switch change (or the reverse).
– Before an IP services image-to-IP base image master switch change, delete the private-VLAN configuration from the existing stack master. (CSCee06802)
- Port configuration information is lost when changing from switchport to no switchport modes on Catalyst 3750 switches.
This is the expected behavior of the offline configuration (provisioning) feature. There is no workaround. (CSCee12431)
- When connected to the router through an auxiliary port in a session to a Cisco EtherSwitch service module, the service module session fails when you enter the shutdown and the no shutdown interface configuration commands on the service module router interface.
– Connect to the router through the console port, and open a session to the service module. (CSCeh01250) (Cisco EtherSwitch service modules)
- If one switch in a stack of Catalyst 3750 switches requires more time than the other switches to find a bootable image, it might miss the stack master election window. However, even if the switch does not participate in the stack master election, it will join the stack as a member.
The workaround is to copy the bootable image to the parent directory or first directory. (CSCei69329)
- When the path cost to the root bridge is equal from a port on a stacked root and a port on a non stack root, the BLK port is not chosen correctly in the stack when the designated bridge priority changes. This problem appears on switches running in PVST, Rapid-PVST, and MST modes.
The workaround is to assign a lower path cost to the forwarding port. (CSCsd95246)
- When a stack of 3750 switches is configured with a Cross-Stack EtherChannel and one of the physical ports in the EtherChannel has a link-up or a link-down event, the stack might transmit duplicate packets across the EtherChannel. The problem occurs during the very brief interval while the switch stack is adjusting the EtherChannel for changing conditions and adapting the load balance algorithm to the new set of active physical ports.
This can but does not always occur during link flaps and does not last for more than a few milliseconds. This problem can happen for cross-stack EtherChannels with the mode set to ON or LACP.
There is no workaround. No manual intervention is needed. The problem corrects itself within a short interval after the link flap as all the switches in the stack synchronize with the new load-balance configuration. (CSCse75508)
- If a new member switch joins a switch stack within 30 seconds of a command to copy the switch configuration to the running configuration of the stack master being entered, the new member might not get the latest running configuration and might not operate properly.
The workaround is to reboot the new member switch. Use the remote command all show run privileged EXEC command to compare the running configurations of the stack members. (CSCsf31301)
- The error message DOT1X_SWITCH-5-ERR_VLAN_NOT_FOUND might appear for a switch stack under these conditions:
– A supplicant is authenticated on at least one port.
– A new member joins a switch stack.
You can use one of these workarounds:
– Enter the shutdown and the no shutdown interface configuration commands to reset the port.
– Remove and reconfigure the VLAN. (CSCsi26444)
- In a mixed stack of Catalyst 3750 switches and Catalyst 3750-E switches, when the stack reloads, the Catalyst 3750-E might not become stack master, even it has a higher switch priority set.
The workaround is to check the flash. If it contains many files, remove the unnecessary ones. Check the lost and found directory in flash and if there are many files, delete them. To check the number of files use the fsck flash: command. (CSCsi69447)
- A stack member switch might fail to bundle Layer 2 protocol tunnel ports into a port channel when you have followed these steps:
1. You configure a Layer 2 protocol tunnel port on the master switch.
2. You configure a Layer 2 protocol tunnel port on the member switch.
3. You add the port channel to the Layer 2 protocol tunnel port on the master switch.
4. You add the port channel to the Layer 2 protocol tunnel port on the member switch.
After this sequence of steps, the member port might stay suspended.
The workaround is to configure the port on the member switch as a Layer 2 protocol tunnel and at the same time also as a port channel. For example:
- After a stack bootup, the spanning tree state of a port that has IEEE 802.1x enabled might be blocked, even when the port is in the authenticated state. This can occur on a voice port where the Port Fast feature is enabled.
The workaround is to enter a shutdown interface configuration command followed by a no shutdown command on the port in the blocked state. (CSCsl64124)
- When a switch stack is running 802.1x single host mode authentication and has filter-ID or per-user policy maps applied to an interface, these policies are removed if a master switchover occurs. Even though the output from the show ip access-list privileged EXEC command includes these ACLs, the policies are not applied.
The workaround it to enter a shutdown and then a no shutdown interface configuration command on the interface. (CSCsx70643) (Catalyst 3750 switch)
- When the switch stack is in the HSRP active state and a master changeover occurs, you cannot ping the stack by using an HSRP virtual IP address.
There is no workaround.(CSCth00938) (Catalyst 3750 and 2960-S switches)
Trunking
- The switch treats frames received with mixed encapsulation (IEEE 802.1Q and Inter-Switch Link [ISL]) as frames with FCS errors, increments the error counters, and the port LED blinks amber. This happens when an ISL-unaware device receives an ISL-encapsulated packet and forwards the frame to an IEEE 802.1Q trunk interface.
There is no workaround. (CSCdz33708)
- IP traffic with IP options set is sometimes leaked on a trunk port. For example, a trunk port is a member of an IP multicast group in VLAN X but is not a member in VLAN Y. If VLAN Y is the output interface for the multicast route entry assigned to the multicast group and an interface in VLAN Y belongs to the same multicast group, the IP-option traffic received on an input VLAN interface other than one in VLAN Y is sent on the trunk port in VLAN Y because the trunk port is forwarding in VLAN Y, even though the port has no group membership in VLAN Y.
There is no workaround. (CSCdz42909).
- If a Catalyst 3750 switch stack is connected to a designated bridge and the root port of the switch stack is on a different switch than the alternate root port, changing the port priority of the designated ports on the designated bridge has no effect on the root port selection for the Catalyst 3750 switch stack.
There is no workaround. (CSCea40988)
- For trunk ports or access ports configured with IEEE 802.1Q tagging, inconsistent statistics might appear in the show interfaces counters privileged EXEC command output. Valid IEEE 802.1Q frames of 64 to 66 bytes are correctly forwarded even though the port LED blinks amber, and the frames are not counted on the interface statistics.
VLAN
- If the number of VLANs times the number of trunk ports exceeds the recommended limit of 13,000, the switch can fail.
The workaround is to reduce the number of VLANs or trunks. (CSCeb31087)
- (Catalyst 3750 or 3560 switches) A CPUHOG message sometimes appears when you configure a private VLAN. Enable port security on one or more of the ports affected by the private VLAN configuration.
There is no workaround. (CSCed71422)
- (Catalyst 3750) When you apply a per-VLAN quality of service (QoS), per-port policer policy-map to a VLAN Switched Virtual Interface (SVI), the second-level (child) policy-map in use cannot be re-used by another policy-map.
The workaround is to define another policy-map name for the second-level policy-map with the same configuration to be used for another policy-map. (CSCef47377)
- When dynamic ARP inspection is configured on a VLAN, and the ARP traffic on a port in the VLAN is within the configured rate limit, the port might go into an error-disabled state.
The workaround is to configure the burst interval to more than 1 second. (CSCse06827, Catalyst 3750 switches only)
- When line rate traffic is passing through a dynamic port, and you enter the switchport access vlan dynamic interface configuration command for a range of ports, the VLANs might not be assigned correctly. One or more VLANs with a null ID appears in the MAC address table instead.
The workaround is to enter the switchport access vlan dynamic interface configuration command separately on each port. (CSCsi26392)
- When many VLANs are configured on the switch, high CPU utilization occurs when many links are flapping at the same time.
The workaround is to remove unnecessary VLANs to reduce CPU utilization when many links are flapping. (CSCtl04815)
Important Notes
- Switch Stack Notes
- Catalyst 2960-S Control Plane Protection
- Catalyst 2960-S Control Plane Protection
- Device Manager Notes
Switch Stack Notes
- Always power off a switch before adding or removing it from a switch stack.
- Catalyst 3560 switches do not support switch stacking. However, the show processes privileged EXEC command still lists stack-related processes. This occurs because these switches share common code with other switches that do support stacking.
- Catalyst 3750 switches running Cisco IOS Release 12.2(25)SEB are compatible with Cisco EtherSwitch service modules running Cisco IOS Release 12.2(25)EZ. Catalyst 3750 switches and Cisco EtherSwitch service modules can be in the same switch stack. In this switch stack, the Catalyst 3750 switch or the Cisco EtherSwitch service module can be the stack master.
Catalyst 2960-S Control Plane Protection
Catalyst 2960-S switches internally support up to 16 different control plane queues. Each queue is dedicated to handling specific protocol packets and is assigned a priority level. For example, STP, routed, and logged packets are sent to three different control plane queues, which are prioritized in corresponding order, with STP having the highest priority. Each queue is allocated a certain amount of processing time based on its priority. The processing-time ratio between low-level functions and high-level functions is allocated as 1-to-2. Therefore, the control plane logic dynamically adjusts the CPU utilization to handle high-level management functions as well as punted traffic (up to the maximum CPU processing capacity). Basic control plane functions, such as the CLI, are not overwhelmed by functions such logging or forwarding of packets.
Cisco IOS Notes
- If the switch requests information from the Cisco Secure Access Control Server (ACS) and the message exchange times out because the server does not respond, a message similar to this appears:
If this message appears, check that there is network connectivity between the switch and the ACS. You should also check that the switch has been properly configured as an AAA client on the ACS
- If the switch has interfaces with automatic QoS for voice over IP (VoIP) configured and you upgrade the switch software to Cisco IOS Release 12.2(40)SE (or later), when you enter the auto qos voip cisco-phone interface configuration command on another interface, you might see this message:
If this happens, enter the no auto qos voip cisco-phone interface command on all interface with this configuration to delete it. Then enter the auto qos voip cisco-phone command on each of these interfaces to reapply the configuration.
Device Manager Notes
- You cannot create and manage switch clusters through the device manager. To create and manage switch clusters, use the CLI or Cisco Network Assistant.
- When the switch is running a localized version of the device manager, the switch displays settings and status only in English letters. Input entries on the switch can only be in English letters.
- For device manager session on Internet Explorer, popup messages in Japanese or in simplified Chinese can appear as garbled text. These messages appear properly if your operating system is in Japanese or Chinese
- The Legend on the device manager incorrectly includes the 1000BASE-BX SFP module.
- We recommend this browser setting to speed up the time needed to display the device manager from Microsoft Internet Explorer.
From Microsoft Internet Explorer:
1. Choose Tools > Internet Options .
2. Click Settings in the “Temporary Internet files” area.
3. From the Settings window, choose Automatically .
5. Click OK to exit the Internet Options window.
- The HTTP server interface must be enabled to display the device manager. By default, the HTTP server is enabled on the switch. Use the show running-config privileged EXEC command to see if the HTTP server is enabled or disabled.
If you are not using the default method of authentication (the enable password), you need to configure the HTTP server interface with the method of authentication used on the switch
Beginning in privileged EXEC mode, follow these steps to configure the HTTP server interface:
The device manager uses the HTTP protocol (the default is port 80) and the default method of authentication (the enable password) to communicate with the switch through any of its Ethernet ports and to allow switch management from a standard web browser.
If you change the HTTP port, you must include the new port number when you enter the IP address in the browser Location or Address field (for example, http://10.1.126.45:184 where 184 is the new HTTP port number). You should write down the port number through which you are connected. Use care when changing the switch IP information.
Cisco Bug Search Tool
The Bug Search Tool (BST), which is the online successor to Bug Toolkit, is designed to improve the effectiveness in network risk management and device troubleshooting. The BST allows partners and customers to search for software bugs based on product, release, and keyword, and aggregates key data such as bug details, product, and version. The tool has a provision to filter bugs based on credentials to provide external and internal bug views for the search input.
To view the details of a caveat listed in this document:
1. Access the BST (use your Cisco user ID and password) at https://tools.cisco.com/bugsearch/ .
Open Caveats
Unless otherwise noted, these caveats apply to the Catalyst 3750, 3560, 2960-S, and 2960 switches and to Cisco EtherSwitch service modules:
Cisco Network Assistant displays the LED ports with a light blue color for all switches in a stack that have the Catalyst 3750G-48PS switch as part of the stack.
Mediatrace does not report statistics on the initiator under these conditions:
– The responder is a mixed switch stack with a Catalyst 3750 as the master switch
– The ingress interface on the responder from the initiator is on a member switch.
The workaround is to ensure that the mediatrace ingress and egress connections are on the stack master or to configure a Catalyst 3750-E or 3750-X as the stack master and then reload the switch stack.
On a switch stack, when an IP phone connected to a member switch has its MAC address authorized using the critical voice VLAN feature, if a master changeover occurs, the voice traffic is dropped. Drop entries for the IP phone appear in the MAC address table management (MATM) table. This occurs because the switch initially drops the voice traffic before reauthenticating critical voice VLAN traffic. The dropped entries are removed when critical voice VLAN authentication occurs.
There is no workaround. The dropped entries are removed when the IP phone is reauthenticated.
ASP now uses a device classifier, which determines the type of device that is connected to the switch. As a result, ASP has no control over the protocol type that is used to detect the device. Therefore, the protocol detection controls are deprecated. When you enter the macro auto global control detection command, the protocol does not show up in the running configuration; however, the filter-spec command is shown in the output.
There is no workaround. To see the deprecated commands, enter the show running config deprecated global and interface configuration command.
The global power inline consumption default 15400 command fails to restrict the power consumption of a PoE+ port 15.4 W.
The workaround is to use the power inline consumption 15400 command in interface configuration mode.
In a switch stack, multicast traffic can be lost for up to 60 seconds when the master switch is reloaded. Because the platform does not support multicast non-stop-forwarding (NSF), the time before traffic re-convergence after a switchover can vary.
When sampled NetFlow is configured with the command ip flow monitor fm-3 in , the sampler tables are not exported to the collector.
The workaround is to use the configuration command ip flow monitor fm-3 sampler s-1 in .
While configuring VLAN load balancing using Resilient Ethernet Protocol (REP) on ether channel interface where bundled interfaces are spread across member stack switches, the MAC address flaps when the ether channel state changes from open to alternate.
System memory may get exhausted on standalone switches with 64 MB of DRAM and stackable switches with 128 MB of DRAM when 802.1x authentication is enabled concurrently with other features. A switch stack of Catalyst 3750v2 switches with more than five members may exhaust system memory and become inoperable.
The workaround is to limit stacks to five members or fewer.
After you upgrade the switch to 12.2(58)SE or later, a Catalyst 3560-C switch with 64MB of DRAM might display low memory on the console.
The workaround is to limit the memory that is used by different features on the switch, if this release is required. You can reduce memory usage by minimizing the number of trunk ports and VLANs in use on the switch.
When a configured macro runs twice in quick succession by the ASP, the following traceback may be seen.
AAA-6-BADHDL invalid hdl AAA ID 174287, hdl 1C000BAA, retired -Process= "ASP Process Creation", ipl= 0, pid= 324
-Traceback= 37CCBCz 277BECz 27A6DCz 64344z 66074z 6614Cz 1C28F38z 1C2368CzThis is seen when there is a quick link flap during NIC initialization when a PC (in a PXE boot environment) is directly connected to a switch. In such cases, macros need to run at least twice in quick succession. The above traceback is not harmful but is expected
The switch experiences continuous traceback and CPU hog when you configure the scheduler max-task-time 500 command.
Resolved Caveats
- Caveats Resolved in Cisco IOS Release 15.0(2)SE12
- Caveats Resolved in Cisco IOS Release 15.0(2)SE11
- Caveats Resolved in Cisco IOS Release 15.0(2)SE10a
- Caveats Resolved in Cisco IOS Release 15.0(2)SE10
- Caveats Resolved in Cisco IOS Release 15.0(2)SE9
- Caveats Resolved in Cisco IOS Release 15.0(2)SE8
- Caveats Resolved in Cisco IOS Release 15.0(2)SE7
- Caveats Resolved in Cisco IOS Release 15.0(2)SE6
- Caveats Resolved in Cisco IOS Release 15.0(2)SE5
- Caveats Resolved in Cisco IOS Release 15.0(2)SE4
- Caveats Resolved in Cisco IOS Release 15.0(2)SE3
- Caveats Resolved in Cisco IOS Release 15.0(2)SE2
- Caveats Resolved in Cisco IOS Release 15.0(2)SE1
- Caveats Resolved in Cisco IOS Release 15.0(2)SE
Caveats Resolved in Cisco IOS Release 15.0(2)SE12
Use the Bug Search Toolkit to view the details of a caveat listed in this section. For more information about the BST, go to https://tools.cisco.com/bugsearch/ .
Caveats Resolved in Cisco IOS Release 15.0(2)SE11
Use the Bug Search Toolkit to view the details of a caveat listed in this section. For more information about the BST, go to https://tools.cisco.com/bugsearch/ .
Caveats Resolved in Cisco IOS Release 15.0(2)SE10a
Use the Bug Search Toolkit to view the details of a caveat listed in this section. For more information about the BST, go to https://tools.cisco.com/bugsearch/ .
Caveats Resolved in Cisco IOS Release 15.0(2)SE10
Use the Bug Search Toolkit to view the details of a caveat listed in this section. For more information about the BST, go to https://tools.cisco.com/bugsearch/ .
Caveats Resolved in Cisco IOS Release 15.0(2)SE9
Use the Bug Search Toolkit to view the details of a caveat listed in this section. For more information about the BST, go to https://tools.cisco.com/bugsearch/ .
Caveats Resolved in Cisco IOS Release 15.0(2)SE8
Use the Bug Search Toolkit to view the details of a caveat listed in this section. For more information about the BST, go to https://tools.cisco.com/bugsearch/ .
Caveats Resolved in Cisco IOS Release 15.0(2)SE7
Telnet sessions that are incompletely established may not time out after a period of inactivity, leading to eventual exhaustion of available VTY lines .
When the telnet client initiates a telnet session to IOS Server with a small TCP window size (<2) ( rcvwnd in the client tcp, sndwnd in the server side), the target lines are hung for ever. It needs to be manually cleared via clear tcp only (clear line does not work). This issue happens for both VTY/TTY sessions.
The workaround is that it needs to be manually cleared via clear tcp tcb 0xXXXX only (clear line does not work).
0xXXXX corresponds to hung line.
The process Kron CLI Process show tech-support password | redirect tftp crashes because of memory corruption. The configuration is as show below:
kron occurrence Daily-writeNet at 11:50 recurring
kron occurrence Daily-showtech at 13:50 recurring
cli show tech-support password | redirect tftp://194.25.4.197/tech/ms1-ag9!
cli copy running-config rcp://c@194.25.4.197/ms1-ag9The cli copy running-config rcp://c@194.25.4.197/ms1-ag9 command works, but the cli show tech-support password | redirect tftp://194.25.4.197/tech/ms1-ag9 command crashes.
When rsh command constructs are used within Tclscript, Tcl fails to send the router hostname which causes the rsh command constructs to fail authorization to a remote router.
An EEM script that executes on a syslog event causes the Cisco router to fail with the following error message.
000199: *Aug 23 16:49:32 GMT: %BGP-5-ADJCHANGE: neighbor x.x.x.x Up
Frame pointer 0x30CF1428, PC = 0x148FDF84
UNIX-EXT-SIGNAL: Segmentation fault(11), Process = EEM ED Syslog
1#07279b80de945124c720ef5414c32a90 :10000000+48FDF84 :10000000+48FE400 :10000
000+4B819C8 :10000000+4B81964 :10000000+F5FAD8 :10000000+F5FD10 :10000000+F5FE
F0 :10000000+F5FF94 :10000000+F60608When running the command show snmp engineID on a switch with WS-X45-SUP7-E running cat4500e-universalk9.SPA.03.01.00.SG.150-1.XO.bin, it shows same engineID 800000090300000000000000 from different switches. It seems that the switch has picked up interface Fa1 macaddress as its engineID.
Local SNMP engineID: 800000090300000000000000
FastEthernet1 is down, line protocol is down
Hardware is RP management port, address is 0000.0000.0000 (bia 0000.0000.0000)The workaround is to manually configure snmp engineID from cli.
When a 1 gig sfp is inserted in a fuller stack with sierra as master, running the sh inventory command does not display the inserted sfp details of the member switch.
Topology used is stack with sierra as master and fuller as member (both are 48 ports).
The Privilege commands are not appearing in the configuration of a Catalyst switch.
When you enter the privilege interface level 3 switchport port-security mac-address sticky command and save the configuration, the command is not visible in neither the startup configuration nor the running configuration. However, privilege level 3 users can view the command and can use it. If you reload the switch, the command is still is not visible in the configuration and also becomes unavailable to the privilege level 3 users.
The workaround is to use the aaa authorization global configuration command to access the commands available for a particular user from the AAA server.
A Cisco Catalyst 3750X switch experiences a memory leak when trying use applications like webauth , web_exec and so on over secure communication (https).
The workaround is to disable https (secure communication) and use http for HTTP requests.
On the Cisco enhanced EtherSwitch service module (SM-ES2-24P), running the logging source-interface # command, does not set the source interface for syslog messages sent to a syslog server.
In a Catalyst 3750X switch stack, the switches experience a slow performance with the following message. Sometimes the switch stops responding and is not recovered until power cycling.
%SUPQ-4-CPUHB_RECV_STARVE: Still seeing receive queue stuck after throttling
You may also observe the following messages when the problem occurs.
%PLATFORM_RPC-3-MSG_THROTTLED: RPC Msg Dropped by throttle mechanism
%XDR-6-XDRIPCNOTIFY: Message not sent to slot X because of IPC error timeout. Disabling linecard. (Expected during linecard OIR)
The issue is observed in switches running 12.2(58)SE or later. It also includes 15.0SE releases and 15.2E releases.
The workaround is to configure a longer logging interval. For example,
ip access-list logging interval <value>
If the issue persists after setting a longer logging interval, you must power cycle the switch.
In a switch stack consisting of Catalyst 2960S switches running 15.0(2)SE4, the MAC address tables on all the stack members are not synchronized with the master switch. This issue is observed when the number of member ports is higher than 4.
The workaround is to configure the missing MAC addresses manually.
When configuring VLANs on 3750X stacked switches, the CLI experiences a delayed or slow response.
The workaround is to configure the VTP domain name with VTP enabled.
A change in the behaviour of DHCP client is observed between 15.0(2)SE2 and 15.0(2)SE4 releases.
On a stack of four WS-C3750X-48PF-S switches running IOS "c3750e-universalk9-mz.150-2.SE5.bin", the CPU Utilization is 99%, majorly due to the process " ASP Process Crea ". The output is as shown:
b-la1-013-sw-01#sho proc cpu sort
CPU utilization for five seconds: 99%/0%; one minute: 99%; five minutes: 84%
--More-- PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
363 99416 3304 30089 50.39% 43.54% 22.12% 0 ASP Process Crea
10 843481803 98980536 8521 18.55% 18.03% 18.08% 0 Hulc LED Process
When trying to remove the macros by running the command " no macro auto global processing ", the CPU comes back to normal but the master switch crashes.
The workaround is to reload the stack. The CPU remains low for a while. Removing the macros at this time does not cause the master switch to crash.
After system reload, ip ssh source-interface shows in startup-config but disappears from
running-config. This is seen in both the scenarios as mentioned below.
1. Configure ip ssh source-interface <interface> CLI
(config)#ip ssh source-interface gi0/3
2. In show run output, it will show ip ssh source-interface <interface> CLI
3. Configure same <interface> (which is configured in ip ssh source-interface CLI) from switch-port to routed-port.
4. Step 4: In show run output, it will not show ip ssh source-interface <interface> CLI
1. Configure some <interface> from switch-port to routed-port.
2. Configure “ip ssh source-interface <interface>” CLI with same interface mentioned in step 1
i.e. (config)#ip ssh source-interface gi0/3
3. In show run ” output, it will show “ ip ssh source-interface <interface> ” CLI configured
4. Save the configuration and reload
5. After reload, in show run output, it will not show “ ip ssh source-interface <interface> ” CLI
The workaround is to re-configure ip ssh source-interface <interface> CLI.
When around 500 Vlans are configured on a switch running IOS 15.0(2)SE5, and then if the interface is moved down or up, the switch shows high CPU Utilization, with maximum usage by 802.1x switch process for 3 minutes.
The issue is not seen on switches running IOS 15.0(2)SE4
The workaround is to disable the device sensor as no macro auto monitor
Designated port on the Root Bridge experiences a block forward for 30 seconds. This issue occurs because the message-time (the period of time a packet is alive in the network) is almost equal to max-age (the period of time a packet is allowed to stay in the network). When message-time >= max-age, the switch receives an agedMsg on the forwarding port which moves the port to a blocking state.
The lightweight wireless access point macro applied to an interface which has both CDP and LLDP enabled flaps continuously. The CDP neighbor devices are discovered initially on the Gi0 interface of the AP and then after a few seconds, the neighbour devices are discovered on the main interface and the sub-interface (Gi0 and Gi0.1) of the AP. After some time, CDP neighborship times out for the Gi0 interface and the macro configuration for $LINKUP == "NO" event is applied on the switch interface.
The workaround is to disable LLDP on the switch interface.
When port-security is configured on all ports and when the end host is moved, the mac address table is out of sync.
The workaround is to clear the mac address table.
When Resilient Ethernet Protocol (REP) is running, CPU usage is high during a failover.
When a PC with 802.1x capability is connected to the IP phone, and the PC boots up, the IP Phone sends CDP port UP to the switch, which restarts 802.1x authentication process. The Switch deletes running 802.1x authentication process and starts over upon receiving CDP port UP from the IP phone. It makes authentication process fail on the machines which can only complete it in first run.
On Cisco IOS Release 15.0(2)SE6, the PS-FAN falls to FAUTY status after upgrading the IOS software from Cisco IOS Release 15.0(2)SE5. The show env stack command displays the following output:
Temperature Value: 35 Degree Celsius
Yellow Threshold : 46 Degree Celsius
Red Threshold : 60 Degree Celsius
Temperature Value: 34 Degree Celsius
Yellow Threshold : 46 Degree Celsius
Red Threshold : 60 Degree Celsius
The workaround is to downgrade to Cisco IOS Release 15.0(2)SE5 or to use the latest release which has fix for this issue.
With EX90/EX60 is configured to communicate over the data vlan, EX cannot get ip via DHCP over the data Vlan. This is because switch expects the packet to arrive on voice vlan from EX, but EX is sending packets on data vlan. All DHCP requests get dropped at the switch. Hence EX is not able to get the ip address.
The workaround is to disable one of the following:
– Voice Vlan on the interface (remove voice vlan config from the interface)
Due to a timing issue, the port channel member port on the slave switch of the stack loops during boot up. The issue occurs only on the member port that is configured as the first port in a cross-stack EtherChannel configuration and when Nexus devices are connected to Cisco devices. Due to Link Aggregation Control Protocol (LACP) graceful convergence, when both the devices are up and in sync (S) state, Cisco devices start transmitting even before the devices get onto collecting (C) state. This causes the port to be pulled down by the Nexus devices. When this happens during boot up, the EtherChannel hardware programming for the port is cleared even when the port is bundled in the port-channel.
The workaround is to enter the shutdown/no shutdown command on the port-channel interface or disable lacp graceful-convergence on the port-channel on peer devices.
When a switch stack is configured in VTP client mode with VTP password, the show command for the stack master displays the VTP operating mode as client, whereas the member switches display the VTP operating mode as server.
The workaround is to remove the VTP password.
10G link convergence is better than 1G convergence during link pull or link down. When the interface is lost in a port channel the flow switch over to the backup link is faster for 10G uplink when compared to a 1G uplink. This is because interface state polling is faster for 10G uplink than 1G uplink.
Caveats Resolved in Cisco IOS Release 15.0(2)SE6
On stack switches, the first switch is configured as client and the other switch is configured as DHCP server and TFTP server. When you reload the first switch, the auto configuration does not start.
- CSCto13462 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and c3560C405EX)
In a network that consists of two DHCP clients with same client id and different mac addresses, the DHCP server reloads when one of the clients releases its DHCP address.
- CSCtr38563 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
Switch fails when a secondary IP address is configured on a VLAN interface.
- CSCts43759 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
The CPU usage increases when you configure the local proxy Address Resolution Protocol (ARP) feature on a Switch Virtual Interface (SVI).
The workaround is after you configure the SVI, remove the local proxy ARP configuration by entering the no ip local-proxy-arp command, and reconfigure it by entering the ip local-proxy-arp command.
- CSCts80209 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
A switch configured with login quiet-mode resets when you enter the login block-for or no login block-for commands.
There is no workaround. Nevertheless, to avoid a reset, do not enter the login block or no login block-for commands.
- CSCtz14399 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
The TCP stack of Cisco IOS Software impose a vulnerability caused by terminating the TCP connections incorrectly. This vulnerability can be exploited by allowing an unauthenticated, remote attacker to send a crafted sequence of TCP ACK and FIN packets to an affected device thereby causing an ACK storm which results in excessive network utilization and high CPU usage.
The workaround is to use the clear tcp tcb 0x<tcb_num> , where the hexadecimal value is the address of the TCB with a connection state of LASTACK in show tcp brief command.
When you configure Flex Link on stacks containing interfaces from different switches, the interfaces start flapping continuously.
The workaround is to remove the Flex Link configuration from the interfaces.
Port-channel interface flaps while adding or removing a VLAN from the trunk on a port-channel interface if one or more port members are not in P or D states.
The workaround is to shut down the port members which are not in P or D states and make the VLAN changes.
- CSCue95644 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
When you upgrade a device to a Cisco IOS or Cisco IOS XE release that supports Type 4 passwords, enable secret passwords are stored using a Type 4 hash which can be more easily compromised than a Type 5 password.
The workaround is to configure enable secret command on an IOS device without Type 4 support, copy the resulting Type 5 password, and paste it into the appropriate command on the upgraded IOS device.
In a stack of Catalyst Switches, port security enabled ports block all the network traffic through them. Using the sh mac address-table command shows that the mac address is learned as static on the master switch, whereas the member switches do not have this mac address on their mac address table.
Configuring logging buffered [size] command with large buffer size causes the switch to experience an out of memory or low memory condition.
The workaround is to reduce the logging buffer allocation using the CLI.
- CSCug47095 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960c405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
During the SNMP walk, the vlanTrunkPortDynamicStatus object in the CISCO-VTP-MIB module shows " notTrunking(2)” for the members of Port-channel trunk ports.
The workaround is to use the CLI to get the correct values.
The DHCP Snooping or the IP Device Tracking (IPDT) feature does not work when you upgrade the switch to Cisco IOS release 15.0(2) SE5. The host IP address is not displayed when you run the sh auth sess int det command.
The switch port goes in to the err-disabled state due to port security violations.
The workaround is to run the no switchport command on the interface.
- CSCuh45966 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
Device under test (DUT) fails with traceback when you enter the configure replace target-url command. The issue occurs when the following message is forwarded to forward_formatted_msg_to_logger() API.
% eula should be accepted for non-interactive management for license-level = ipservices (stack3-1-3I-1-2)In a switch stack, if a stack member is connected to a Meru access point that requires 802.3at or 29.5W POE+ inline power, the connection over 802.3at POE+ fails.
The workaround is to move all the affected POE+ devices to the stack master.
When the switch is run on the IPBase license and when you enter the show sdm prefer command, the IPV6 entries are not displayed though the IPV6 feature is supported.
The stacked switch setup fails when you change or remove an existing password while the relayed console waits for the authentication prompt.
The workaround is to reduce the number of changes to the password in the console or VTY when the relayed console waits for the authentication prompt.
In a Cisco Catalyst Switch stack of 8 member switches, a memory leak is observed in the HRPC pm request handler process. The issue occurs after reloading the stack members or after online insertion and removal (OIR) of the transceivers that are DOM capable.
When you enable the Address Resolution Protocol (ARP) retry feature on the switch, the CPU usage increases.
When VLAN Trunk Protocol (VTP) version 3 is configured on stacked switches, the inconsistency in VTP mode is observed between the master switch and the member switch. When you run the show vtp status command, the master switch shows the status as Server for VLAN and Transparent for Multiple Spanning Tree (MST), and the member switch shows the status as Primary Server for both VLAN and MST.
The workaround is to configure the switch to VTP version 2 and then reconfigure the switch to VTP version 3.
The Web Cache Communication Protocol (WCCP) traffic drops when you reload the master switch with the stack switch.
In a topology in which a Catalyst 3750X switch acts as the multicast router, a receiver constantly sends join messages to a multicast group (*,G) before the source starts sending the multicast traffic. When the source starts sending traffic to the multicast group, an (S,G) is created and some of the initial packets sent by the source are lost. Once the (S,G) is programmed for the traffic sent by the source, all the subsequent multicast traffic reaches the receiver.
- CSCuj48700 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
A switch reboots unexpectedly while using dot1x authentication with IP Device Tracking (IPDT) enabled. If ip device tracking probe { delay delay } is configured and the switch is operating near the maximum IPDT limit of 2048 hosts, there is a probability that a host may have its delay timer started, but released before it expires.
Use one of the following workarounds:
– Keep the number of hosts less than 2048.
– Disable dot1x authentication, which in turn disables IP HOST TRACK process.
- CSCuj54648 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960-LM, 3750, 3560, and 3560C405)
The blocked port on a Catalyst Switch, receives and forwards a malformed TCP packet thereby causing the packet to loop continuously in the network and flooding to all the ports of the VLAN.
Use one of the following workarounds:
– Enter the shut or no shut command on any of the ports in the topology.
– Change the Spanning Tree Protocol (STP) priority of any of the switches in the topology.
– Downgrade the switch to 12.2(35)SE5 and the malformed TCP packet is dropped on the blocked port.
CSCuj65057 (Catalyst Switches 2960-SF, 2960-S, and 3750)
When you configure per-VRF on a AAA TACACS+ server group, the ip vrf forwarding command does not appear in the running configuration after reloading the stack master. This issue takes place only in stack configurations.
The workaround is to use vrf definition command instead of ip vrf command to configure per-VRF.
- CSCuj77254 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
Access Control List (ACL) configured on guest VLAN interface for 802.1X unauthenticated clients do not get applied.
The workaround is to configure the ACL on the dot1x port itself instead of the guest VLAN interface.
After performing a shut or no shut on the ports of a Catalyst Switch, the status of some of the ports are displayed as Not Connected , even if they are connected to a remote device.
The workaround is to perform a shut or no shut on the affected ports.
In the switch running earlier to Cisco IOS software release 12.2(52)SE, the switch displays “Error loading flash” messages when restarted.
The workaround is to upgrade the switch to Cisco IOS software release 12.2(52)SE or later.
The switch reboots if the shutdown and no shutdown commands are repeatedly entered for the alternating ports in an 8-node Resilient Ethernet Protocol (REP) ring segment. The following error message is displayed:
- CSCul17159 (Catalyst Switches 2960, 2960-LANLITE, 2960-SF, 2960C405, 2960C405EX, 2960-LM, 2960-S, 2960-SM, 3750, 3560, 3560C405, and 3560C405EX)
In response to an NTP control request, the offset value in the reply packet received from a Catalyst 3560X/E switch running on 12.2(58)SE or later is different from the offset value in a packet received from a switch running on 12.2(55)SE or earlier.
The workaround is to downgrade the switch to 12.2(55)SE or earlier.
When you repeatedly run the shut and no shut command in the alternating ports on a 8 node REP ring, the stack member with REP secondary edge port drops the multicast traffic for 20 to 50 seconds.
When a new switch is added to the stack, and if the stack has the Hot Standby Router Protocol (HSRP) configured, the newly added member switch fails.
Caveats Resolved in Cisco IOS Release 15.0(2)SE5
In Policy Based Routing (PBR), if the first match clause is removed, the packets are forwarded to the next hop IP address of the second match clause. This feature, which previously showed errors, is now functioning properly.
There is no workaround needed.
(LAN Base) ACLs applied to outbound traffic on the switch virtual interface (SVI) do not work.
If a 100BaseFX-SFP module is used in the switch, data packets on this interface may drop over this link.
The workaround is to reinsert the module into the switch.
After a master switch failure, the member link within an LACP-enabled EtherChannel fails to recover.
The workaround is to enter the shutdown command followed by the no shutdown command, which will recover the failed links.
The "HULC DOT1X Process" leaks memory on the switch stack member. Sometimes the following
log message is displayed:
%AAA-3-ACCT_LOW_MEM_UID_FAIL: AAA unable to create UID for incoming calls due to insufficient processor memoryThe command power inline port 2x-mode was not supported on the switch. This has now been fixed.
Cyclic Redundancy Check (CRC) errors appear on switch with Fast Ethernet module operating at 10 Mb half-duplex mode.
CPU usage goes above 90% when Internet Group Management Protocol (IGMP) version 3 report packets are sent to the switch which has IGMP version 2 configured on the switch virtual interface.
The workaround is to either disable multicast fast convergence or configure IGMP version 3 on switch virtual interface.
TACACS+ single connect authentication request from a switch stack takes around 10 to 12 minutes to failover to secondary server after the primary TACACS server is unreachable.
The workaround is to disable TACACS+ single connect configuration on the switch.
Switch runs out of memory within few seconds of configuring the level <n> show spanning-tree active/detail privilege EXEC command.
Switches that run Cisco IOS Release 15.0(02.01.12)SE4 do not support 8k MAC addresses with IPv6 templates.
There is no workaround. 8k MAC address are supported on the dual-ipv4-and-ipv6 VLAN template introduced in Cisco IOS release 15.0(02.01.12)SE05.
Web authentication does not work.
MACsec link traffic drops periodically.
In a switch stack where EnergyWise is enabled, memory leak is observed when the show energy wise children privileged EXEC command is entered or when the
cewEntEnergyUsageobject ID is polled.Caveats Resolved in Cisco IOS Release 15.0(2)SE4
When the switch is started using TACACS+ configurations, the CPU utilization increases to 100% and the VTY device does not work.
The workaround is to remove the TACACS+ configurations and restart the switch.
The ipAddrEntry value in the IP Address Table shows an interface index that is not exposed by the ifEntry Object ID.
Internal VLANs are displayed when the show snmp mib ifmib ifindex command is entered or the SNMP is queried for the ipMIB object.
The workaround is to check if the displayed VLANs are internal and then to hide them.
Caveats Resolved in Cisco IOS Release 15.0(2)SE3
CPU usage is high when an SNMP Walk of the Address Resolution Protocol (ARP) table is performed.
The workaround is to implement SNMP view using the following commands:
snmp-server view cutdown iso included
snmp-server view cutdown at excluded
snmp-server view cutdown ip.22 excluded
snmp-server community public view cutdown ro
snmp-server community private view cutdown rw
If an ACL is configured on a router VTY line for ingress traffic, the ACL is applied for egress traffic also. As a result, egress traffic to another router on an SSH connection is blocked.
The workaround is to permit egress traffic to the specific destination router using the permit tcp host <destination router IP address> eq 0 any interface configuration command.
The device connected to the switch crashes when a CDP data frame is processed. The
SYS-2-FREEFREEandSYS-6-MTRACEmessages are displayed.The workaround is to disable CDP using the no cdp run global configuration command. This workaround is not applicable if the connected device relies on or supports a phone or voice network.
The service module fails when the TestPortAsicRingLoopback online diagnostic test is run.
Memory leak is seen in the switch when it sends CDP, LLDP or DHCP traffic and when the link flaps.
The workaround is to apply protocol filters to the device sensor output by entering the following global configuration commands:
device-sensor filter-spec dhcp exclude all
device-sensor filter-spec lldp exclude all
device-sensor filter-spec cdp exclude all
If the memory leak continues in the "DHCPD Receive" process, disable the built-in DHCP server by entering the no service dhcp global configuration command.
Spurious traps observed periodically on removal of power to RPS.
STP loop occurs on Flexstack connected by parallel links when a link state is changed on Flexlink port.
The workaround is to change the switch to root bridge.
Policy Based Routing (PBR) entry on the switch does not become inactive even after the PBR route's next hop is lost. The traffic continues to take failed PBR path instead of the next available best path.
Duplex status configured on 100BASE-FX SFP interface changes from full to half when shut/no shut command is run on the interface.
The workaround is to delete the duplex full configuration and configure again.
If a policy map attached to the switch interface is modified then the corresponding QoS policy works incorrectly.
The workaround is to delete the policy map, create a new policy map and then attach it to the interface.
The switch blackholes traffic redirected by Web Cache Communication Protocol (WCCP). This issue occurs when the WCCP cache engine is shut down and the cache is not cleared.
The workaround is to use Cisco IOS Release 12.2(55) or later.
When native VLAN is configured on the trunk or when switchport trunk native vlan 99 is configured on the interface, spanning-tree instance is not created for native VLAN.
The workaround is to keep VLAN1 as a native on the trunk. In Cisco IOS Release15.0(2) SE, dot1.x is enabled by default and causes authentication fail in the native VLAN. This results in pm_vp_statemachine not triggering any event to spanning tree. To disable dot1x internally, run the no macro auto monitor command. The stp instance is created for native vlan 99 after running the show and no show command on the interface.
When a member of 3750 stack is reloaded, the uplink trunk connected to Catalyst 4500 switch becomes non-trunk causing STP issues on the switch. The STP reports the stack port as root port instead of Gi2/0/1.
When a member of 3750 stack with fiber SFP uplinks is reloaded, it results in STP issues on the stack and the internal stack ports on the switch becomes the root port.
CRC errors are reportedwhen traffic is sent from the peer ports of a switch.
The Web Cache Communication Protocol (WCCP) traffics are not redirected after reloading the switch.
The workaround is to remove the WCCP redirects command from the interface and then add them back on the interface.
TCP fragmented packets cannot be sent for SPAN monitor session.
The work around is to use the egress span iso of the ingress span and span the malformed TCP packets to span destination port as there are no classification checks in the egress interface for parse fail conditions.
On the Catalyst 2960S switch stack, when the login block command is configured and the running config is saved using the wr command on the master, it brings the master down. When the running config is saved on the new master , the following lines are displayed on entering the show running-config command.
ip access-list extended sl_def_acl
When the secret password is configured, the password is not saved. The default password is used as the secret password.
The workaround is to use the default password to login and then change the password.
The device sensor related memory leak is still visible in DHCPD Receive, CDP Protocol, and Net Background processes even after disabling the device sensor feature by entering the no macro auto monitor command. This symptom is observed in Cisco IOS 15.0(2)SE1 Release, 2960-S, dhcp, cdp traffic, and link flapping.
The known workaround is to enter the no service dhcp command if the switch is not a DHCP server and configure the device sensor as follows:
device-sensor filter-spec cdp exclude all
Caveats Resolved in Cisco IOS Release 15.0(2)SE2
When a client fails to authenticate in the multi-auth mode, the session continues to be active indefinitely.
The workaround is to enter the clear authentication sessions privileged EXEC command to clear information for all authentication manager sessions.
The down-when-looped interface configuration command is not supported with default speed or with 1000BaseT advertisements on the gigabit medium independent interface (GMII interface). This is because the down-when-looped feature and 1000BaseT advertisements both make use of the "next page" function as defined in IEEE 802.3, clause 28 and may result in the link staying down.
Caveats Resolved in Cisco IOS Release 15.0(2)SE1
When using SNMP v3, the switch unexpectedly reloads when it encounters the snmp_free_variable_element.
The Resource Reservation Protocol (RSVP) feature in Cisco IOS Software and Cisco IOS XE Software contains a DoS vulnerability.
Cisco has released free software updates that address this vulnerability. There are no workarounds available to mitigate this vulnerability.
This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130327-rsvp
Note The March 27, 2013, Cisco IOS Software Security Advisory bundled publication includes seven Cisco Security Advisories. All advisories address vulnerabilities in Cisco IOS Software. Each Cisco IOS Software Security Advisory lists the Cisco IOS Software releases that correct the vulnerability or vulnerabilities detailed in the advisory as well as the Cisco IOS Software releases that correct all Cisco IOS Software vulnerabilities in the March 2013 bundled publication.
Individual publication links are in “Cisco Event Response: Semiannual Cisco IOS Software Security Advisory Bundled Publication” at the following link:
http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_mar13.html
The Cisco IOS Software implementation of the virtual routing and forwarding (VRF) aware network address translation (NAT) feature contains a vulnerability when translating IP packets that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.
Cisco has released free software updates that address this vulnerability. Workarounds that mitigate this vulnerability are not available.
This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130327-nat
Note The March 27, 2013, Cisco IOS Software Security Advisory bundled publication includes seven Cisco Security Advisories. All advisories address vulnerabilities in Cisco IOS Software. Each Cisco IOS Software Security Advisory lists the Cisco IOS Software releases that correct the vulnerability or vulnerabilities detailed in the advisory as well as the Cisco IOS Software releases that correct all Cisco IOS Software vulnerabilities in the March 2013 bundled publication.
Individual publication links are in “Cisco Event Response: Semiannual Cisco IOS Software Security Advisory Bundled Publication” at the following link:
http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_mar13.html
When two traps are generated by two separate processes, the switch fails if one process is suspended while the other process updates variables used by the first process.
The workaround is to disable all SNMP traps.
If a redundant power supply (RSP) switchover occurs during a bulk configuration synchronization, some of the line configurations might disappear.
The workaround is to reapply the line configurations.
Beginning with Cisco IOS Release 12.2(52)SE, the device tracking table could map only one IP address to a single MAC address. This restriction has been removed, and several IP addresses can now be mapped to a single MAC address.
The show ip dhcp pool command displays a large number of leased addresses.
The workaround is to turn off ip dhcp remember and reload the switch.
The following warning messages might be displayed during the boot process even when a RADIUS or a TACACS server have been defined:
The traceroute command returns the error message:
The secure copy feature (copy: source-filename scp: destination-filename command) does not work.
This problem occurs when the Enterprise Policy Manager (EPM) for a device connected to an interface is authorized in closed mode and no policies are configured or downloaded. If no port ACL is configured, the auth-default access control list (ACL) is applied to the switch. If another device is connected to this device, restricted VLAN (authentication event interface configuration command) is enabled on the port. The Application Control Engine (ACE) is not configured to permit traffic originating from the connected device, and IP packets are dropped.
The workaround is to configure a port ACL to allow IP traffic for the specific IP range for the connected devices on the interface.
When Catalyst 3750 switch or Catalyst 3560 is configured as a Layer 3 switch with local connected hosts, the switches drop large IPv6 traffic loads intended for local connected hosts.
The workaround is not to globally configure IPv4 VRF.
If a Catalyst 2960 switch boots with Cisco IOS Release 12.2(50)SE5 or later, a Catalyst 3750 switch that is connected by a trunk port to the Catalyst 2960 switch cannot receive the Generic Attribution Registration Protocol (GARP) data packets from the Catalyst 2960 switch.
The workaround is to perform the following actions:
- Run the Catalyst 2960 switch on Cisco IOS Release 12.2(25)SEE or 12.2(53)SE2.
- Clear the Address Resolution Protocol (ARP) on the connected device.
- Enter the switchport noneg command to specify that Dynamic Trunking Protocol (DTP) negotiation packets are not sent to the Layer 2 interface.
- Ping from the Catalyst 2960 switch to the connected device.
- Use the line-proto-delay command to control Switch Virtual Interface (SVI) timing.
When ipl=5, the Catalyst 2960 switch receives the malloc failure message of 20 bytes, and traceback occurs due to interrupt level.
A Platform assert failure message is displayed on the switch. Traceback occurs after deleting the static mac-address table
The workaround is to set the dynamic mac-address table and to ensure that the return value of the API that allocates SD is checked correctly.
Customers unable to appy Quality of Service (QoS) policy-map on interface on more than 4 ports on different ASIC on a switch. This issue is common to Catalyst 2960G, 3560G, and 3750G switches having more than one ASIC.
When the ip rsvp snooping command is enabled on a Layer 2 environment, the switch stops forwarding the metadata packets.
IPv6 packets are forwarded between two isolated ports in the same private VLAN.
When the master switch (Switch A) is reloaded or loses power and rejoins the stack as a member switch, any traffic stream that exits Switch A is dropped because the newly joined member is not able to establish an Address Resolution Protocol (ARP) entry for the next hop router or switch. Debugs confirm that Switch A does not send a GARP or ARP for the next hop, though traffic continues to be sent to the switch.
The workaround is to add a static ARP. Ping the destination from Switch A to force the ARP to respond.
Local web authorization and HTTP services on the switch do not respond because of a web authorization resource limitation in the system. The resource limitation is normally caused by incorrectly terminated HTTP or TCP sessions.
These are possible workarounds and are not guaranteed to solve the problem:
– Enter the ip admission max-login-attempts privileged EXEC command to increase the number of maximum login attempts allowed per user.
– If the web authorization module is intercepting HTTP sessions from web clients in an attempt to authorize them, try using a different browser.
– Eliminate background processes that use HTTP transport.
The CISCO_LAST_RESORT_AUTO_SMARTPORT macro is applied to any device for which there is no built-in or user-defined macro, regardless of whether the device supports CDP, Link Layer Discovery Protocol (LLDP), or DHCP. To ensure that a device is not running a discovery protocol that matches the device to a built-in or user-defined macro, the switch waits about 120 seconds before applying the CISCO_LAST_RESORT_AUTO_SMARTPORT macro. The macro is applied to devices such as PCs, laptops, and printers. You do not need to configure MAC operationally unique identifier (OUI)-based triggers and map these triggers to a macro for these devices.
The Smart Install client feature in Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
Affected devices that are configured as Smart Install clients are vulnerable.
Cisco has released free software updates that address this vulnerability. There are no workarounds for devices that have the Smart Install client feature enabled.
This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20130327-smartinstall
If an interface is configured with the switchport port-security maximum 1 vlan command, the following error message is displayed:
%PORT_SECURITY-2-PSECURE_VIOLATION: Security violation occurred, caused by MAC address XXXX.XXXX.XXXX on port <interface>The flash memory is corrupted when you format the flash manually.
The workaround is to reload the switch. (Note that this will erase the flash memory, and you will need to reload the software image using TFTP, a USB drive, or a serial cable.
VLAN-based QoS is not available on interfaces on the WS-C3560CG switches.
If the Performance Monitor cache is displayed (using the show performance monitor cache command) and you attempt to stop the command output display by entering the q keyword, there is an unusually long delay before the output is stopped.
The workaround is to enter the term len 0 privileged EXEC command so that all command outputs are displayed without any breaks.
Cisco TrustSec Media Access Control Security (MACsec) cannot be configured on uplink ports. MACsec interface commands are not accepted on the switch except when you enter the sap pmk key modelist no-encap command. This issue is seen on switch model WS-C3560CG for interface range GigabitEthernet0/9 to GigabitEthernet0/10.
The workaround is to configure Cisco TrustSec MACsec the on RJ45 Gigabit Ethernet ports for interface range GigabitEthernet0/1 to GigabitEthernet0/8. There is no workaround for Cisco TrustSec MACsec configuration on Gigabit Ethernet optical links.
The device-sensor accounting global configuration command is not available.
Caveats Resolved in Cisco IOS Release 15.0(2)SE
When a Catalyst 2960S series switch is booted up, a large number of Yeti2S88gMdioWr: Unknown status for write operation messages may be written to the console. Although the error messages may substantially increase bootup time, the switch is fully functional after Cisco IOS boots.
The workaround is to power cycle the switch for a quick recovery. This is a software issue and the switch does not require replacement.
When a switchover occurs in a switch stack, the host session information is lost.
The workaround is to reauthenticate all the clients.
When the show epm session summary or show epm command is entered from an SSH or telnet session and another command is entered from the console, the switch might unexpectedly reset and generate crash information.
The workaround is to enter both commands from the same session, either SSH/telnet or console.
The switch might occasionally reload after experiencing a CPU overload, regardless of what process is overloading the CPU.
The switch downloads the running IOS image from the TFTP server and reboots even though the same image is currently loaded and running.
Cisco IOS Software and Cisco IOS XE Software contain a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. An attacker could exploit this vulnerability by sending a crafted request to an affected device that has the DHCP version 6 (DHCPv6) server feature enabled, causing a reload.
Cisco has released free software updates that address this vulnerability. This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20120926-dhcpv6
When an interface is configured with the mls qos command, traffic is not matched by port-based QoS ACLs that use the range option.
The workaround is to is to configure the switch using the single port eq keyword. Alternatively, you can configure the trust under class-default setting for the same policy-map that uses the acl-range option.
In a switch stack, you cannot establish a console session with a member switch when an ACL is applied to the VTY lines.
The workaround is to use the following procedure when you apply an ACL to line vty 0 4 and line vty 5 15:
1. Create the vty ACL and permit the 127 network.
2. Append the vrf-also keyword to the configured access-class inbound.
In a switch stack, the show interface command shows incorrect values for output drops.
The workaround is to use the show platform port-asic stats drops command to see the correct values.
The archive download feature does not work if the flash contains an “update” directory. This situation is likely to occur if a previous download failed or was interrupted and the “update”” directory is still left in the flash.
The workaround is to delete the “update” directory in the flash before starting the archive download.
A static route that has the next hop set to null0 is removed when the master switch is changed in a switch stack configuration. This situation occurs when the switch is stacked and the static route is advertised by the network 0.0.0.0 command.
The workaround is to use the ip summary-address eigrp as-number ip-address mask command to set the IP summary aggregate address for the interface through which the next hop can be found.
The Catalyst 4500E series switch with Supervisor Engine 7L-E contains a denial of service (DoS) vulnerability when processing specially crafted packets that can cause a reload of the device.
Cisco has released free software updates that address this vulnerability.
Workarounds that mitigate this vulnerability are not available.
This advisory is available at the following link:
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20120926-ecc
When ports from each switch in a switch stack are bundled together to form an uplink port channel, Multicast VLAN Registration (MVR) streams are sent only to the switch with the active member in the port channel.
The workaround is to use Internet Group Management Protocol (IGMP) snooping.
When a device is moved from one port to another in a switch stack, the SNMP data generated for the move event is incorrect.
The workaround is to ensure that the uplink to the core network is configured on the master switch (for example, a 1/0/x port).
OSPFv3 neighbors might flap because of the way the switch handles IPv6 traffic destined for well-known IPv6 multicast addresses.
Users connecting to the network through a device configured for web proxy authentication may experience a web authentication failure.
There is no workaround. Use the clear tcp tcb command to release the HTTP Proxy Server process.
Using the dot1x default command on a port disables access control on the port and resets the values of the authentication host-mode and authentication timer reauthenticate commands to the default values.
The workaround is to avoid using the dot1x default command and set various dot1x parameters individually. You can also reconfigure the parameters that were changed after you entered the dot1x default command.
The switch drops Layer 3 multicast traffic received from a Layer 2 port channel on a switch virtual interface (SVI) that is associated with a VPN Routing and Forwarding (VRF) instance.
The workaround is to flap the ingress physical interface, the SVI, or the port channel.
In a switch stack setup after you reload a member switch, a multilayer switching (MLS) class of service (CoS) configuration command with a specified value such as mls qos cos 7 on the slave switch does not function anymore. This situation impacts untagged IP and Layer 2 packets.
The workaround is to ensure that when you configure a service policy on an interface, an interface default level CoS is also configured. You can use mls trust qos cos command in interface configuration mode.
Frame check sequence (FCS) errors occur when the switch receives jumbo frames (greater than 9000 bytes) on downlink ports.
When using the switchport port-security maximum 1 vlan access command, if an IP-phone with a personal computer connected to it is connected to an access port with port security, a security violation will occur on the interface. This type of message is displayed on the console:
%PORT_SECURITY-2-PSECURE_VIOLATION: Security violation occurred, caused by MAC address XXXX.XXXX.XXXX on port FastEthernet0/1.Here is a sample configuration:
The workaround is to remove the line switchport port-security maximum 1 vlan access.
The switch does not correctly detect a loopback when the switch port on an authenticated IP phone is looped to a port configured and authenticated with dot1x security, even when bpduguard is configured on the interface. This situation can result in 100 percent CPU utilization and degraded switch performance.
The workaround is to configure the interface with the authentication open command or to configure authentication mac-move permit on the switch.
If a new port is added to an etherchannel on a switch using DAI or IPDT, ARP packets that ingress the port are lost.
The workaround is to save the configuration and reload the switch. Alternatively, configure the switch by entering the no macro auto monitor command followed by the macro auto monitor command after the port is bundled for the first time.
The system memory on some switches (standalone switches with 64MB of DRAM, and stackable switches of more than 5 members with 128MB of DRAM each) may be exhausted when 802.1x authentication is enabled concurrently with other features.
The workaround for 3750v2 stacks is to limit the setup to 5 switches. If more then 5 switches are required in a stack, keep the number of VLANs and enabled features as low as possible. The workaround for 2960 switches with 64MB of DRAM is to maintain 1MB of memory free all the time.
Documentation Updates
Information Added to the “Configuring Interface Characteristics” Chapter
In the “Configuring Interface Characteristics” chapter, this new section was added:
Universal Power over Ethernet Support
Cisco Universal Power over Ethernet (UPoE) is a Cisco proprietary technology that extends the IEEE 802.3 PoE standard to provide up to 60W of power over standard Ethernet cabling infrastructure (Class E or better). UPoE power negotiation uses Cisco Discovery Protocol (CDP) and Link Layer Discovery Protocol (LLDP), to which proprietary type-length-value (TLV) elements have been introduced. UPoE is available only when both the powered device (PD) and the power sourcing equipment (PSE) support these additional TLVs.
The Catalyst 2960-C and 3560-C switches have both PD and PSE capabilities. These switches support UPoE on one uplink interface at a time and negotiate power of up to 60 W from a parent PSE. On the downlink interfaces, the switches are capable of sourcing IEEE 802.3af PoE only.
Guidelines and Limitations
- Because CDP is enabled on the switch by default, no special configuration is required to enable UPoE negotiation. If you want to used LLDP instead of CDP, disable CDP and enable LLP in global configuration mode, followed by the shutdown/no shutdown command sequence on the interface of parent switch.
- In general, the switch cannot negotiate UPoE power when both uplinks are connected to a PoE-capable PSE. The exceptions are when one of the uplinks is connected to a data-only interface on the PSE or when the first uplink has negotiated UPoE power. When the first uplink negotiates UPoE power, the second uplink behaves like a data-only interface.
- Table 8 shows the valid configurations when the switch is connected to a UPoE-capable PSE.
Table 8 Catalyst 2960-C and 3560-C Switch Connected to UPoE-Capable PSE
- Table 9 shows the amount of power available for pass-through PoE when the switch has negotiated UPoE.
Related Documentation
User documentation in HTML format includes the latest documentation updates and might be more current than the complete book PDF available on Cisco.com.
These documents provide complete information about the Catalyst 3750, 3560, 2975, 2960-S and 2960 switches and the Cisco EtherSwitch service modules and are available at Cisco.com:
http://www.cisco.com/en/US/products/hw/switches/ps5023/tsd_products_support_series_home.html
http://www.cisco.com/en/US/products/hw/switches/ps5528/tsd_products_support_series_home.html
http://www.cisco.com/en/US/products/ps10081/tsd_products_support_series_home.html
http://www.cisco.com/en/US/products/ps6406/tsd_products_support_series_home.htmlThese documents provide complete information about the Catalyst 3750 switches and the Cisco EtherSwitch service modules:
- Catalyst 3750 Switch Software Configuration Guide
- Catalyst 3750 Switch Command Reference
- Catalyst 3750, 3560, 3550, 2975, 2970, 2960, and 2960-S Switch System Message Guide
- Catalyst 3750 Switch Hardware Installation Guide
- Catalyst 3750 Getting Started Guide
- Catalyst 3750 Integrated Wireless LAN Controller Switch Getting Started Guide
- Regulatory Compliance and Safety Information for the Catalyst 3750 Switch
These documents provide complete information about the Catalyst 3750G Integrated Wireless LAN Controller Switch and the integrated wireless LAN controller and are available at cisco.com:
- Catalyst 3750 Integrated Wireless LAN Controller Switch Getting Started Guide
- Release Notes for Cisco Wireless LAN Controller and Lightweight Access Point, Release 4.0.x.0
- Cisco Wireless LAN Controller Configuration Guide, Release 4.0
- Cisco W ireless LAN Controller Command Reference, Release 4.0
These documents provide complete information about the Catalyst 3560 switches:
- Catalyst 3560 Switch Software Configuration Guide
- Catalyst 3560 Switch Command Reference
- Catalyst 3750, 3560, 3550, 2975, 2970, 2960, and 2960-S Switch System Message Guide
- Catalyst 3560 Switch Hardware Installation Guide
- Catalyst 3560 Switch Getting Started Guide
- Regulatory Compliance and Safety Information for the Catalyst 3560 Switch
These documents provide complete information about the Catalyst 2960 and 2960-S switches and are available on Cisco.com:
- Catalyst 2960 and 2960-S Switch Software Configuration Guide
- Catalyst 2960 and 2960-S Switch Command Reference
- Catalyst 3750, 3560, 3550, 2975, 2970, 2960, and 2960-S Switch System Message Guide
- Catalyst 2960-S Switch Hardware Installation Guide
- Catalyst 2960-S Switch Getting Started Guide
- Catalyst 2960 Switch Hardware Installation Guide
- Catalyst 2960 Switch Getting Started Guide
- Catalyst 2960 Switch Getting Started Guide —available in English, simplified Chinese, French, German, Italian, Japanese, and Spanish
- Regulatory Compliance and Safety Information for the Catalyst 2960 and 2960-S Switch
For other information about related products, see these documents:
- Smart Install Configuration Guide
- Auto Smartports Configuration Guide
- Cisco EnergyWise Configuration Guide
- Getting Started with Cisco Network Assistant
- Release Notes for Cisco Network Assistant
- Cisco RPS 300 Redundant Power System Hardware Installation Guide
- Cisco RPS 675 Redundant Power System Hardware Installation Guide
- For more information about the Network Admission Control (NAC) features, see the Network Admission Control Software Configuration Guide
- Information about Cisco SFP, SFP+, and GBIC modules is available from this Cisco.com site:
http://www.cisco.com/en/US/products/hw/modules/ps5455/prod_installation_guides_list.htmlSFP compatibility matrix documents are available from this Cisco.com site:
http://www.cisco.com/en/US/products/hw/modules/ps5455/products_device_support_tables_list
.htmlObtaining Documentation and Submitting a Service Request
For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What’s New in Cisco Product Documentation , which also lists all new and revised Cisco technical documentation:
http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.htmlSubscribe to the What’s New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service and Cisco currently supports RSS version 2.0.
This document is to be used in conjunction with the documents listed in the “Obtaining Documentation and Submitting a Service Request” section.
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks . Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1721R)
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
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