Troubleshooting Port Problems - Cisco 9134 - MDS Multilayer Fabric Switch Troubleshooting Manual

Chapter 8 Troubleshooting Ports
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m

Troubleshooting Port Problems

Start the debugging with the command show hardware internal fc-mac port port link-status. See the
"Useful Commands at the FC-MAC Level" section on page 8-11
information.
You must use the attach module CLI command to access the FC-MAC show commands.
Note
When this command executes, it performs the following checks in the order shown here and displays the
appropriate information:
1.
2.
3.
4.
5.
Note
6.
Note
7.
OL-9285-05
Checks whether the port was declared a failure because of an exception. For additional information,
use the show process exceptionlog CLI command.
Checks whether the port is administratively enabled.
Checks whether the physical link state is up. If the state is up, then it does the following:
Checks for possible completion of the FLOGI process.
–
FLOGI is transparent to the MAC driver and is based on some expected configuration. The
Note
MAC driver assumes that the FLOGI process is completed.
Checks for error counters.
–
Checks whether the port is in the offline state. The port goes to the offline state if the FLOGI or ELP
(in case of auto mode) on the port does not succeed.
Checks for pause state. A pause state is in an intermediate state (as maintained by the FC-MAC
driver) after the link goes down and before the port is enabled by the Port Manager.
The link reinitializes after a link down event is initiated only if enable is issued by the Port
Manager.
Checks for the presence of SFP/GBIC. If present, FC-MAC checks for loss of signal. The loss of
signal state indicates either the physical connectivity between two end ports is bad or there is a
transmit fault in the SFP. Use the show hardware internal fc-mac port port gbic-info command to
check for the transmit fault.
You must use the attach module CLI command to access the FC-MAC show commands.
Checks for the speed and sync state of the port. If the port is in the speed initialization state, then:
–
Auto speed is in progress
–
Waiting for stable sync
is displayed if the MAC state indicates a loss of synchronization. In auto
–
Sync not acquired
mode, this state is not necessarily an error. In any case, check the speed capabilities and
configuration at both ends.
is displayed if the port is in automode.
is displayed if the port is configured for a fixed speed.
Cisco MDS 9000 Family Troubleshooting Guide, Release 3.x
Common Problems with Port Interfaces
to understand how to use the FC-MAC
8-15