You can run manual loopback tests to identify hardware errors in the
data path in the switching or services modules, and the control path in the
supervisor modules. External loopback tests send and receive FC2 frames to and
from the same port or between two ports.
You need to connect a cable (or a plug) to loop the Rx port to the Tx
port before running the test. If you are testing to and from the same port, you
need a special loop cable. If you are testing to and from different ports, you
can use a regular cable. This test is only available for Fibre Channel
interfaces.
Use the EXEC-level
system
health
external-loopback
interface
interface
command to run this test on demand for external devices connected
to a switch that is part of a long-haul network.
switch# system health external-loopback interface fc 3/1
This will shut the requested interfaces Do you want to continue (y/n)? [n] y
External loopback test on interface fc3/1 was successful.
Sent 1 received 1 frames
Use the EXEC-level
system
health
external-loopback
source
interface
destination
interface
interface
command to run this test on demand between two ports on the
switch.
switch# system health external-loopback source interface fc 3/1 destination interface fc 3/2
This will shut the requested interfaces Do you want to continue (y/n)? [n] y
External loopback test on interface fc3/1 and interface fc3/2 was successful.
Sent 1 received 1 frames
Use the EXEC-level
system
health
external-loopback
interface
frame-count
command to run this test on demand for external devices connected
to a switch that is part of a long-haul network and override the frame count
configured on the switch.
switch# system health external-loopback interface fc 3/1 frame-count 10
This will shut the requested interfaces Do you want to continue (y/n)? [n] y
External loopback test on interface fc3/1 was successful.
Sent 1 received 1 frames
Use the EXEC-level
system
health
external-loopback
interface
frame-length
command to run this test on demand for external devices connected
to a switch that is part of a long-haul network and override the frame length
configured on the switch.
switch# system health external-loopback interface fc 3/1 frame-length 64
This will shut the requested interfaces Do you want to continue (y/n)? [n] y
External loopback test on interface fc3/1 was successful.
Sent 1 received 1 frames
Use the
system
health
external-loopback
interface
force
command to shut down the required interface directly without a
back out confirmation.
switch# system health external-loopback interface fc 3/1 force
External loopback test on interface fc3/1 was successful.
Sent 1 received 1 frames
Note |
If the test fails to complete successfully, the software analyzes
the failure and prints the following error: External loopback test on interface
fc 7/2 failed. Failure reason: Failed to loopback, analysis complete Failed
device ID 3 on module 1
|