Port Channel Restriction; Trunking Overview; Initial Troubleshooting Checklist; Chapter 11 Port Channel And Trunking - Cisco Nexus 1000V Troubleshooting Manual

Initial Troubleshooting Checklist

Port Channel Restriction

The following are port channel restrictions.
•
•

Trunking Overview

Trunking, also known as VLAN trunking, enables interconnected ports to transmit and receive frames in
more than one VLAN over the same physical link.
Trunking and port channels function as follows:
•
•

Initial Troubleshooting Checklist

Use the following checklist to begin troubleshooting port channel and trunking issues:
Checklist
Use the show port-channel compatibility-parameters CLI command to determine port
channel requirements.
Ensure that all interfaces in the port channel have the same destination device for Link
Aggregation Control Protocol (LACP) channels. By using the Asymmetric Port Channel
(APC) feature in the Cisco Nexus 1000V, ports in an ON mode channel can be connected
to two different destination devices.
Note
Verify that either side of a port channel is connected to the same number of interfaces.
Verify that each interface is connected to the same type of interface on the other side.
Verify that all required VLANs on a trunk port are in the allowed VLAN list.
Verify that all the members trying to form a port channel are on the same module.
Verify that the port channel configuration is present in the profile used by the physical
ports.
Configure APC if the ports are connected to different upstream switches.
If the upstream switch does not support port channels, make sure that you haveto configure
APC in the profile. In addition, make sure that you have no more than two ports in the APC.
The following commands help you to troubleshoot port channels and trunking:
•
•
Cisco Nexus 1000V Troubleshooting Guide, Release 5.2(1)SV3(1.1)
11-2
Port channels do not support ACLs.
Port channels do not support NetFlow.
Port channels enable several physical links to be combined into one aggregated logical link.
Trunking enables a link to carry (trunk) multiple VLAN traffic.
APC is supported only on mode channels. It is not supported for LACP channels.
show port-channel summary
show port-channel internal event-history interface port-channel channel-number
Chapter 11 Port Channels and Trunking
OL-31593-01