Initial Port Troubleshooting Checklist; Viewing Port Information - Cisco Nexus 9000 Series Troubleshooting Manual

Initial Port Troubleshooting Checklist

• Before you begin configuring a device, make sure that the modules in the chassis are functioning as
• When configuring dedicated ports in a port group, follow these port mode guidelines:
• There are no licensing requirements for port configuration in Cisco NX-OS.

Initial Port Troubleshooting Checklist

Begin troubleshooting the port configuration by checking the following issues:
Checklist
Check the physical media to ensure that there are no damaged parts.
Verify that the SFP (small form-factor pluggable) devices in use are those authorized by Cisco
and that they are not faulty.
Verify that you have enabled the port by using the no shutdown command.
Use the show interface command to verify the state of the interface. See the Cisco Nexus 9000
Series NX-OS Interfaces Configuration Guide for reasons why a port might be in a down
operational state.
Verify that you have configured a port as dedicated and make sure that you have not connected
to the other three ports in the port group.

Viewing Port Information

You can use the show interface counters command to view port counters. Typically, you only observe
counters while actively troubleshooting, in which case you should first clear the counters to create a baseline.
The values, even if they are high for certain counters, can be meaningless for a port that has been active for
an extended period. Clearing the counters provides a better idea of the link behavior as you begin to
troubleshoot.
Use one of the following commands to clear all port counters or the counters for specified interfaces:
• clear counters interface all
• clear counters interface range
The counters can identify synchronization problems by displaying a significant disparity between received
and transmitted frames.
Use the following commands to gather more information about ports:
Cisco Nexus 9000 Series NX-OS Troubleshooting Guide, Release 7.x
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designed. Use the show module command to verify that a module is OK or active before continuing the
configuration.
• You can configure only the one port in each four-port group in dedicated mode. The other three
ports are not usable and remain shut down.
• If any of the other three ports are enabled, you cannot configure the remaining port in dedicated
mode. The other three ports continue to remain enabled.
Troubleshooting Ports
Done