Troubleshooting and Diagnostics Guide

32 Fabric OS Troubleshooting and Diagnostics Guide
53-1002751-01
Marginal links
3
switch:admin> porterrshow
frames enc crc crc too too bad enc disc link loss loss frjt fbsy
tx rx in err g_eof shrt long eof out c3 fail sync sig
============================================================================
0: 665k 7.0k 0 0 0 0 0 0 6 0 0 1 2 0 0
1: 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0
2: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
3: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
4: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
5: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
6: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
7: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
8: 78 60 0 0 0 0 0 0 7 0 0 3 6 0 0
9: 12 4 0 0 0 0 0 0 3 0 0 1 2 0 0
10: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
11: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
12: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
13: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
14: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
15: 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
16: 665k 7.4k 0 0 0 0 0 0 6 0 0 1 2 0 0
(output truncated)
3. If you suspect a marginal link, isolate the areas by moving the suspected marginal port cable to
a different port on the switch. Reseating of SFPs may also cure marginal port problems.
If the problem stops or goes away, the switch port or the SFP is marginal (proceed to step 6).
If the problem does not stop or go away, see step 7.
4. Run portLoopbackTest on the marginal port. You need an adapter to run the loopback test for
the SFP. Otherwise, run the test on the marginal port using the loopback mode lb=5. Use the
different modes shown in Table 5 to test the port. Refer to the Fabric OS Command Reference
for additional information on this command.
5. Check the results of the loopback test and proceed as follows:
• If the loopback test failed, the port is bad. Replace the port blade or switch.
• If the loopback test did not fail, the SFP was bad.
6. Replace the SFP on the marginal port.
7. Perform the following steps to rule out cabling issues:
a. Insert a new cable in the suspected marginal port.
b. Enter the portErrShow command to determine if a problem still exists.
• If the portErrShow output displays a normal number of generated errors, the issue is
solved.
• If the portErrShow output still displays a high number of generated errors, follow the
troubleshooting procedures for the Host or Storage device in the following section,
“Device login issues”.