Brocade® Product Training

Marginal Link
8
Start
Move suspected marginal
interface media to different
port (See tip #1)
Re-run the failing
application to
replicate the error
(See tip #2)
Does the error
follow?
No
Run crossporttest
in single port mode
Does the test
fail?
Yes
No
Replace with known good
media (See tip #3)
Focus on Nx-Port
(See Note 1)
Yes
Run loopporttest
fporttest, spinfab
or porttest
© 2005 Brocade Communications Systems, Incorporated.
Revision CFP261-02-2005
Chapter 8 - 8
Tip#1 – Interface media consists of GBIC/SFP, or Fibre Channel cable. Move each medium one at a
time. Use porterrshow statistics to determine most likely medium to move 1 st .
Tip#2 – If the original marginal link error was not initiated by I/O activities or POST, then run
crossporttest to verify. While crossporttest is running, check the 8 statistic counts via
errshow, porterrshow or portshow command outputs.
Tip#3 – Always verify that new media is “known good”. If the error was not initiated by I/O
activities or POST, then run crossporttest to verify correction.
Note 1 – You have isolated the problem, it is the Nx_Port (HBA or storage controller card). Use the
Nx_Port utilities to troubleshoot this problem. Suggestion: You may need to verify with the latest
HBA/controller driver before replacing the device. Check the vendor compatibility matrix.
© 2005 Brocade Communications Systems, Incorporated.
Revision CFP261-02-2005
Chapter 8 - 8