Cisco Nexus 1000V Release Notes, Release 4.2(1)SV2(1.1a)
Software Compatibility with VMware
Software Compatibility with Cisco Nexus 1000
Single VMware Data Center Support
Cisco NX-OS Commands Might Differ from Cisco IOS
Layer 2 Switching: No Spanning Tree Protocol
DHCP Not Supported for the Management IP
VM Name Display Length Limitation
Copy Running-Config Startup-Config Command
Error Messages Appear During ESX 4.1.0 Server Bootup
Dynamic Entries Are Not Deleted for a Linux VM
Source Filter TX VLANs Are Missing After the VSM Restarts
Default SSH Inactive Session Timeout
Queueing Policy Cannot Be Changed in Flexible Upgrade Setup
Clear QoS Statistics Fails on the VSM
Platform, Infrastructure, Ports, Port Channel, and Port Profiles
Obtaining Documentation and Submitting a Service Request
Release: NX-OS Release 4.2(1)SV2(1.1a)
This document describes the features, limitations, and bugs for the Cisco Nexus 1000V Release 4.2(1)SV2(1.1a) software. The following is the change history for this document.
Updated the “LACP” section and added the “Upstream Switch Ports” section. |
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The Cisco Nexus 1000V provides a distributed, Layer 2 virtual switch that extends across many virtualized hosts. The Cisco Nexus 1000V manages a data center defined by the vCenter Server. Each server in the data center is represented as a line card in the Cisco Nexus 1000V and can be managed as if it were a line card in a physical Cisco switch.
The Cisco Nexus 1000V consists of the following two components:
The servers that run the Cisco Nexus 1000 VSM and VEM must be in the VMware Hardware Compatibility list. This release of the Cisco Nexus 1000V supports vSphere 4.1.0, 5.0.0, and 5.1.0 release trains. For additional compatibility information, see the Cisco Nexus 1000V Compatibility Information, Release 4.2(1)SV2(1.1a).
Note All virtual machine network adapter types that VMware vSphere supports are supported with the Cisco Nexus 1000. Refer to the VMware documentation when choosing a network adapter. For more information, see the VMware Knowledge Base article #1001805.
This release supports hitless upgrades from Release 4.0(4)SV1(3a) and later releases. Upgrades are supported from 4.0(4)SV1(3) and earlier releases. For additional information, see the Cisco Nexus 1000V Software Upgrade Guide, Release 4.2(1)SV1(5.1).
This section lists the Cisco Nexus 1000V limitations and restrictions.
Table 1 lists the Cisco Nexus 1000V configuration limits.
The Cisco Nexus 1000V can be connected to a single VMware vCenter Server data center object. Note that this virtual data center can span multiple physical data centers.
VMotion of the VSM has the following limitations and restrictions:
For more information about VMotion of VSM, see the Cisco Nexus 1000V Software Installation Guide, Release 4.2(1)SV1(5.1).
The NetFlow configuration has the following support, limitations, and restrictions:
The NetFlow cache table has the following limitation:
Note The cache size that is configured using the CLI defines the number of entries, not the size in bytes. The configured entries are allocated for each processor in the ESX host and the total memory allocated depends on the number of processors.
Port security has the following support, limitations, and restrictions:
Port profiles have the following restrictions or limitations:
The Telnet server is enabled by default.
For information, see the Cisco Nexus 1000V Security Configuration Guide, Release 4.2(1)SV2(1.1).
Only SSH version 2 (SSHv2) is supported.
For information, see the Cisco Nexus 1000V Security Configuration Guide, Release 4.2(1)SV2(1.1).
Be aware that the Cisco NX-OS CLI commands and modes might differ from those commands and modes used in the Cisco IOS software.
For information, see the Cisco Nexus 1000V Command Reference, Release 4.2(1)SV2(1.1).
The Cisco Nexus 1000V forwarding logic is designed to prevent network loops so it does not need to use the Spanning Tree Protocol. Packets that are received from the network on any link connecting the host to the network are not forwarded back to the network by the Cisco Nexus 1000V.
For information about Layer 2 switching, see the Cisco Nexus 1000V Layer 2 Switching Configuration Guide, Release 4.2(1)SV2(1.1).
The Cisco Discovery Protocol (CDP) is enabled globally by default.
CDP runs on all Cisco-manufactured equipment over the data link layer and does the following:
– CDP can discover up to 256 neighbors per port if the port is connected to a hub with 256 connections.
If you disable CDP globally, CDP is also disabled for all interfaces.
For more information about CDP, see the Cisco Nexus 1000V System Management Configuration Guide, Release 4.2(1)SV2(1.1).
DHCP is not supported for the management IP. The management IP must be configured statically.
The Link Aggregation Control Protocol (LACP) is an IEEE standard protocol that aggregates Ethernet links into an EtherChannel.
The Cisco Nexus 1000V has the following restrictions for enabling LACP on ports carrying the control and packet VLANs:
Note These restrictions do not apply to other data ports using LACP.
Note This restriction does not apply if LACP offload is enabled. You can check the LACP offload status by using the show lacp offload status command.
All upstream switch ports must be configured in spanning-tree port type edge trunk mode.
Without spanning-tree PortFast on upstream switch ports, it takes approximately 30 seconds to recover these ports on the upstream switch. Because these ports are carrying control and packet VLANs, the VSM loses connectivity to the VEM.
The following commands are available to use on Cisco upstream switch ports in interface configuration mode:
The Cisco Nexus Virtual Services Appliance (1000V) cannot resolve a domain name or hostname to an IP address.
When the maximum transmission unit (MTU) is configured on an operationally up interface, the interface goes down and comes back up.
When a VEM communicates with Cisco VSG in Layer 3 mode, an additional header with 94 bytes is added to the original packet. You must set the MTU to a minimum of 1594 bytes to accommodate this extra header for any network interface through which the traffic passes between the Cisco Nexus 1000V and the Cisco VSG. These interfaces can include the uplink port profile, the proxy ARP router, or a virtual switch.
VM names for VMs on ESX 4.1 hosts that exceed 21 characters are not displayed correctly on the VSM. When you use a show vservice command that displays the port profile name—for example, the show vservice port brief port-profile port-profile-name command—only VMs with names that are 21 characters or less are displayed correctly. Longer VM names might be truncated or have extra characters appended. Depending on the network adapter, the name length limitation varies. For example:
Note This is a display issue with ESX Release 4.1 only. Use VM names of 21 characters or less to avoid this issue.
Performing an ISSU from Cisco Nexus 1000V Release 4.2(1)SV1(4) or Release 4.2(1)SV1(4a) to Cisco Nexus 1000V Release 4.2(1)SV2(1.1a) using the ISO files is not supported. You must use the kickstart and the system files to perform an ISSU upgrade to Cisco Nexus 1000V Release 4.2(1)SV2(1.1a).
When running the copy running-config startup-config command, do not press the PrtScn key. If you do, the command will abort.
Vssnet-load error messages can occur during a classic ESX 4.1.0 server bootup or restart when the VEM is already installed. The issue occurs while booting up because the path environment variable is not set up correctly, and the system is not able to identify the VMware command. After the system boots up, it is set up correctly and so is the ESX 4.10 system. There is no functional impact of the error messages and they can be ignored.
On a Linux VM that has multiple adapters, a DHCP release packet is sent from an incorrect interface (because of OS functionality) and the DHCP release packet is dropped. As a result, the binding entry is not deleted. This issue is a Linux issue where the packets from all interfaces go out of one interface (which is the default interface). To avoid this issue, put the interfaces in different subnets and make sure that the default gateways for each interface is set.
When a SPAN (erspan-source) session is created and the source interface is configured as a port channel and PVLAN Promiscuous access is programmed, the filter RX is not configured and the configured programmed filter TX is not persistent on VSM reload.
To work around this issue, configure all the primary and secondary VLANs as filter VLANs while using the port channel with PVLAN Promiscuous access as the source interface.
The default SSH inactive session timeout is 30 minutes, but the timeout setting is disabled by default, so the connection remains active. Use the exec-timeout command to explicitly configure the inactive session timeout limit.
Queuing is valid starting from Cisco NX-OS Release 4.2(1)SV1(51). Any queueing configuration that exists on the VSM in an earlier release will stop working. All port profiles that have a queueing configuration cannot be used. If a port is down, it should be moved to a profile without QoS queueing.
When a policy map of type “queuing” has a class map of type “match-any” without any match criteria, and is applied on an interface, a resource pool is not created for that specific class ID. As a result, the collection of statistics fails and no data is sent back to the VSM. To work around this issue, add a match criteria on the empty class map.
This section includes the following topics:
The following are descriptions of the bugs in Cisco Nexus 1000V Release 4.2(1)SV2(1.1a). The ID links you to the Cisco Search Tool.
The following are descriptions of bugs that are resolved in Cisco Nexus 1000V Release 4.2(1)SV2(1.1a). The ID links you to the Cisco Bug Search Tool.
The Cisco Management Information Base (MIB) list includes Cisco proprietary MIBs and many other Internet Engineering Task Force (IETF) standard MIBs. These standard MIBs are defined in Requests for Comments (RFCs). To find specific MIB information, you must examine the Cisco proprietary MIB structure and related IETF-standard MIBs supported by the Cisco Nexus 1000V Series switch.
The MIB Support List is available at the following FTP site:
ftp://ftp.cisco.com/pub/mibs/supportlists/nexus1000v/Nexus1000VMIBSupportList.html
For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a service request, and gathering additional information, see What’s New in Cisco Product Documentation.
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