Troubleshooting Interface Buffer Credits - Cisco MDS 9000 Series Configuration Manual

Troubleshooting Interface Buffer Credits

Troubleshooting Interface Buffer Credits
Use the show interface slot/port bbcredit command to check for discrepency in the buffer-to-buffer credit
values for a specific Fibre Channel interface:
switch# show interface fc2/1 bbcredit
fc2/1 is trunking
Use the show logging onboard interrupt-stats command to view the number of times a port sent extra
R_RDYs or incremented transmit buffer to buffer credits to restore credit counts:
switch# show logging onboard interrupt-stats
.
.
.
-------------------------------------------------------------------------------
INTERRUPT COUNTS INFORMATION FOR DEVICE: FCMAC
-------------------------------------------------------------------------------
Interface|
Range
-------------------------------------------------------------------------------
fc1/1
fc1/1
.
.
.
The IP_FCMAC_INTR_ERR_BB_SCR_INCREMENT counter specifies the number of R_RDYs that were
lost and the IP_FCMAC_INTR_ERR_BB_SCS_RESEND counter specifies the number of frames that were
lost.
Use the show interface port/slot counters details command to check for credit loss recovery:
switch# show interface fc2/1 counters detailed
fc2/1
Cisco MDS 9000 Series Interfaces Configuration Guide, Release 8.x
126
Transmit B2B Credit is 500
Receive B2B Credit is 500
Receive B2B Credit performance buffers is 0
500 receive B2B credit remaining
500 transmit B2B credit remaining
500 low priority transmit B2B credit remaining
500 low priority transmit B2B credit remaining
| Interrupt Counter Name
|
|IP_FCMAC_INTR_ERR_BB_SCR_INCREMENT
|IP_FCMAC_INTR_ERR_BB_SCS_RESEND
4 frames, 304 bytes received
0 class-2 frames, 0 bytes received
0 class-2 discards
0 F_BSY frames, 0 F_RJT frames
generated against class-2 frames
0 port reject frames
4 class-3 frames, 304 bytes received
0 class-f frames, 0 bytes received
0 discards, 0 errors received
0 discards, 0 errors transmitted
4 frames, 304 bytes transmitted
0 class-2 frames, 0 bytes transmitted
4 class-3 frames, 304 bytes transmitted
0 class-3 frames discarded
Configuring Interface Buffers
| | Time Stamp
| Count |MM/DD/YY HH:MM:SS
| |
|1 |01/01/17 20:00:00
|1 |01/01/17 10:00:00