The customer reports that the GE link does not run stably. At a touch of the optical patchcord on the device, the link breaks down. But the optical patchcord is properly connected. The GE link breaks down from time to time and is then resumed after some time.
The optical module connecting both ends of the GE link is eSFP-1310 nm-1.25 Gb/s-�9 dBm-�3 dBm-�20 dBm-LC-single mode-10 km.
Log in to the two devices connected with the GE link and perform the following checks on the two devices after the fault occurs:
1. Check the trap message and the log on the two devices connected with the GE link. Only one device has the link failure information.
2. Conduct the ping test between the two devices. Unidirectional communication occurs.
The fault may be caused by the GE link.
3. Check port information on the device that cannot be successfully pinged. It is found that input errors are increasing, but output errors do not increase.
The fault may be caused by one of the optical fibers of the GE link.
4. Test the optical power of the transmitting device at the end of the problematic fiber with the optical power tester. The transmitting optical power on the interface is �5.3 dBm, which is within the normal range (�9 dBm to �3 dBm).
The interface of the transmitting device cannot be faulty.
5. Test the receiving optical power on the ODF at the end of the problematic fiber with the optical power tester. The receiving optical power is �29.3 dBm, which is much lower than the minimum receiving value �20 dBm.
It is deduced that the fault is caused by the optical patchcord from the transmitting device to the ODF.
6. Prepare to replace the problematic fiber. Fasten the junction of the optical patchcord on the ODF before the replacement. Then it is found that input errors stop increasing and the devices at both ends of the GE link can be successfully pinged.
The fault is fixed. The fault occurs because the optical patchcord in one direction of the GE link is not inserted tightly into the ODF.
When the GE link is not stable or unidirectional communication occurs, check whether any error packet exists on the GE interface; if yes, do as follows to locate the fault:
1. Test the transmitting optical power and the receiving optical power of the two interfaces at the two ends of the GE link.
2. Test the optical fiber link section by section. After the test of each section is complete, check whether the fault is located and rectified; if not, proceed with the test of the next section.