After configurations are performed, optical modules are
inserted, and optical fibers are installed, a link between the leaf switch CE6851
and the spine switch CE12808 fails, and the links on other interfaces are normal.
1. Ping the CE6851 and CE12808 from each other. The ping
2. Check the interface status. It is found that the corresponding interface is
in Error-Down state. Then, check the interface configuration. It is found that
the IP address and route configuration are correct. Therefore, device
configuration errors can be ruled out.
It is suspected that the hardware
Remove the optical fiber of the
faulty link, and observe the fiber ports. No optical signal is transmitted
between the two ends. The possible causes are as follows:
The optical modules at both ends are faulty.
The optical fiber is disconnected.
The card is faulty.
According to the occurrence probability and troubleshooting difficulty, check
the optical modules, optical fiber, and card in sequence.
3. Check whether the optical
modules on the faulty ports are working properly. Because there is no redundant
optical module at the site, remove optical modules of normal ports and insert
the optical modules into the faulty ports. It is found that the link is still
unavailable and no optical signal is transmitted between the two ends. This indicates that the
original optical modules on the faulty ports function properly.
4. Check whether the optical fiber is normal. Remove the optical fiber and
optical modules at both ends of a normal link and insert them into the faulty
ports. It is found that the optical signal is transmitted between the two ends and
the link is recovered.
According to the preceding analysis, the fault is caused
by optical fibers.
According to the handling
process, the optical fiber is faulty and therefore the link is unavailable.
Replace the faulty
optical fibers with new ones.
If similar faults occur,
check the port configurations first. If the configurations are correct, check
whether the hardware is faulty, including optical modules, optical fibers, and