Registers And Counters - Cisco N5K-M1600 - Expansion Module - 6 Ports Troubleshooting Manual

Chapter 2 Troubleshooting FCoE Issues
S e n d d o c u m e n t c o m m e n t s t o n e x u s 5 k - d o c f e e d b a c k @ c i s c o . c o m .
How to enable link pause (flow control) on switch that connects DCBX capable
devices
Link pause is not enabled on the switch ports that are connected to servers. It is necessary to enable link
pause (flow control) on a Nexus 5000 switch that connects DCBX-capable devices.
Possible Cause
If the peer supports PFC TLV with DCBX, then configuring the flowcontrol send on and the flowcontrol
receive on does not enable link pause. You have to disable PFC TLV sent by DCBX on the interface.
To verify this situation, perform one of the following:
•
•
Solution
Use the following commands under the interface ethx/y command to enable link pause instead of PFC
with DCBX capable devices:
•
•
•
How to clear PFC counters
How to clear priority flow counters.
Possible Cause
Currently there are no CLI commands to clear PFC frames (Bug ID is CSCtg08068).
Solution
Although there are no CLI commands to clear the PFC counters, a workaround does exist. You can the
clear interface counters and then enter the show interface ethx/x flowcontrol command to see the PFC
frame count.
The PFC frame count is incremented using the show int ethx/x flowcontrol command. This is a known
Note
bug.

Registers and Counters

Interface level errors
To view any interface level errors, use the show interface counters errors command.
Example:
switch# show interface counters errors
-------------------------------------------------------------------------------
OL-25300-01
Check if the operating state is off using the show interface ethx/y flowcontrol command.
Check if the operating state is on using the show interface ethx/y priority-flow-control command.
no priority-flow-control mode on
flowcontrol receive on
flowcontrol send on
Cisco Nexus 5000 Series Troubleshooting Guide
Registers and Counters
2-15