Problem Description
One ONT connected to the OLT fails to go online. It goes online after other ONTs connected to the same OLT are deactivated.
Handling Process
The roadmap is as follows:
1. Check whether the quality of the ONT line is normal and whether the bit error rate is high.
2. Check whether there is a conflict for ONT identification such as an SN conflict.
3. Check whether there is a rogue ONT.
4. Check whether a port loop exists.
The detailed procedure is as follows:
Step 1 Check the optical path quality of the PON port. It is found that ONT 4 and ONT 7 have an Rx optical power of about –11 dB, while ONT 65 has an Rx optical power of about –26 dB. The optical power difference is large (greater than 15 dB).
Step 2 Query alarms. No alarm indicates a rogue ONT. Therefore, no rogue ONT is connected to the PON port.
Step 3 Query ID and SN information. No SN conflict is found.
Step 4 Query records and alarms. There are records and alarms on a port loop. That is, this port loop causes the ONT go-online failure.
Technical Root Cause
A loop exists on the PON port and therefore the PON port is being deactivated. As a result, the ONT cannot go online.
Solution
1. Check the fiber connections on the PON port and the ONUs connected to the PON port. Determine the ports between which the loop exists, and break the loop.
2. Adjust the Rx optical power of the ONTs connected to the PON port so that the ONTs have similar Rx optical power.
