Release Notes for Catalyst 2960-C and 2960-Plus Switches, Cisco IOS Release 15.2(6)E

Supported Hardware

Device Manager System Requirements

• Hardware Requirements
• Software Requirements

Hardware Requirements

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 2960-C switch, all standby command switches must be Catalyst 2960-C 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 Release 15.2(6)E 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/NetworkAssistant

For more information about Cisco Network Assistant, see the Release Notes for Cisco Network Assistant on Cisco.com.

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.

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.

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.html

You 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.html

Upgrading 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 3 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.

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.

Recovering from a Software Failure

For recovery procedures, see the “Troubleshooting” chapter in the software configuration guide for this release.

Features Introduced in Cisco IOS Release 15.2(6)E2

• There are no new features in this release.

Features Introduced in Cisco IOS Release 15.2(6)E1

• There are no new features in this release.

Features Introduced in Cisco IOS Release 15.2(6)E

• There are no new features in this release.

Cisco IOS Limitations

Unless otherwise noted, these limitations apply to the Catalyst 2960-C and 2960-Plus switches:

• Configuration
• Ethernet
• HSRP
• HSRP
• IP
• IP Telephony
• Power
• QoS
• Smart Install
• SPAN and RSPAN
• Spanning Tree Protocol
• Trunking
• VLAN

Configuration

• 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)

• 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)

• A traceback error occurs if a crypto key is generated after an SSL client session.

There is no workaround. This is a cosmetic error and does not affect the functionality of the switch. (CSCef59331)

• The far-end fault optional facility is not supported on the GLC-GE-100FX SFP module.

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 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)

• When a logging discriminator is configured and applied to a device, memory leak is seen under heavy syslog or debug output. The rate of the leak is dependent on the quantity of logs produced. In extreme cases, the device may crash. As a workaround, disable the logging discriminator on the device. (CSCur45606, CSCur28336)

Ethernet

• 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)

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

• 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)

• 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 Cisco 7905 IP Phone is error-disabled when the phone is connected to wall power.

The workaround is to enable PoE and to configure the switch to recover from the PoE error-disabled state. (CSCsf32300)

• 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)

• 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)

• Incomplete multicast traffic can be seen under either of these conditions:

– 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.

Use one of these workarounds:

– 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

• 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:

There is no impact to switch functionality.

There is no workaround. (CSCtg32101)

RADIUS

• RADIUS change of authorization (COA) reauthorization is not supported on the critical auth VLAN.

There is no workaround. (CSCta05071)

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.

Use one of these workarounds:

– 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)

• 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.

There is no workaround. (CSCth35152)

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)

• 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

• CSCtl60247

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.

There is no workaround.

Trunking

• 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).

• 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.

There is no workaround. (CSCec35100).

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)

• 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)

Device Manager Limitations

• When you are prompted to accept the security certificate and you click No, you only see a blank screen, and the device manager does not launch.

The workaround is to click Yes when you are prompted to accept the certificate. (CSCef45718)

Switch Stack Notes

• Always power off a switch before adding or removing it from a switch stack.

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.

4. Click OK.

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.

• If you use Internet Explorer Version 5.5 and select a URL with a nonstandard port at the end of the address (for example, www. cisco.com:84), you must enter http:// as the URL prefix. Otherwise, you cannot launch the device manager.

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/.

2. Enter the bug ID in the Search For: field.

Open Caveats

None

Caveats Resolved in Cisco IOS Release 15.2(6)E2

Table 5 Resolved Caveats in Cisco IOS Release 15.2(6)E2

Caveats Resolved in Cisco IOS Release 15.2(6)E1

Table 6 Resolved Caveats for Cisco IOS Release 15.2(6)E1

Caveats Resolved in Cisco IOS Release 15.2(6)E

Table 7 Resolved Caveats for Cisco IOS Release 15.2(6)E

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 and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

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