Cisco N5K-M1600 - Expansion Module - 6 Ports Troubleshooting Manual page 35

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 .
PFC
This section includes an overview of how to view standard pause frames, followed by a description of
common problems and their solutions.
Standard pause frames
For ports with standard, non-CNA type host connections, the Nexus 5000 supports standard pause
frames. These are enabled with the interface setting, as shown in the following example:
Example:
switch(config)# interface ethernet 1/16
switch(config-if)# flowcontrol ?
switch(config-if)# flowcontrol receive on
switch(config-if)# flowcontrol send on
To view standard pause frames, use the show interface flowcontrol command.
Example:
switch(config-if)# show interface flowcontrol
-------------------------------------------------------------------------------
Port
-------------------------------------------------------------------------------
Eth1/1
Eth1/2
Eth1/3
Eth1/4
Eth1/5
Eth1/6
Eth1/7
Eth1/8
Eth1/9
Eth1/10
Eth1/11
Eth1/12
Eth1/13
Eth1/14
Eth1/15
Eth1/16
Eth1/17
PFC not negotiated with FCOE-capable adapters (CNA)
Priority flow control (PFC) is not negotiated with FCOE-capable adapters (CNA).
This causes packet drop to be noticed on FCoE traffic from the servers.
Possible Causes
The CNA may not support DCBX and the PFC TLV is not negotiated.
Solution
OL-25300-01
receive Receive pause frames
send Send pause frames
Send FlowControl
admin oper
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
on on
off off
Receive FlowControl
admin oper
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
off off
on on
off off
Cisco Nexus 5000 Series Troubleshooting Guide
RxPause TxPause
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 0
PFC
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