Troubleshooting guide

3. Troubleshooting Functional Failures During Operation
28
Isolate the cause of the problem according to the failure analysis method described
in the following table.
Table 3-13 Failure analysis method for 100BASE-FX [AX1250S] /1000BASE-X problems
No
.
Items to check Cause Action
1 Use the show
interfaces operation
command to display the
failure statistics, and
check whether there is a
count for the following
item for the target line: If
there is a count, see the
Cause and Action
columns.
 Link down
Line quality on
the receiving
side is
degraded.
Check the type of the optical fiber.
If an optical attenuator is used, check the attenuation
value.
Check the cable length. For the cable length, see the
Hardware Instruction Manual.
Check whether the cable is connected correctly (for
example, check for incomplete insertion). For cable
connections, see the Hardware Instruction Manual. Make
sure that the end sections of the cables are clean. and
remove any dirt.
Check whether the transceiver (SFP) is connected
correctly (for example, check for incomplete insertion).
Comply with the segment standard of the remote device.
Check whether the optical level is correct.
2 Use the show
interfaces operation
command to display the
receive-error statistics,
and check whether there
is a count for the following
items for the target line: If
there is a count, see the
Cause and Action
columns.
 CRC errors
 Symbol errors
Check the type of the optical fiber.
If an optical attenuator is used, check the attenuation
value.
Check the cable length. For the cable length, see the
Hardware Instruction Manual.
Check whether the cables are connected correctly (for
example, check for incomplete insertion). For cable
connections, see the Hardware Instruction Manual. Make
sure that the end sections of the cables are clean. If they
are dirty, clean them.
Check that the transceiver (SFP) is connected correctly.
Comply with the segment standard of the remote device.
Check whether the optical level is correct.
3 Use the show
interfaces operation
command to display the
failure statistics, and
check whether there is a
count for the following
item for the target port: If
there is a count, see the
Cause and Action
columns.
 Long frames
Packets
exceeding the
maximum
allowed frame
length are
received.
Adjust the jumbo frame settings to those on the remote
device.