All ONUs connect to active OLT offline

All-ONUs-connect-to-active-OLT-offline
Issue Description
Customer reported that all ONUs connect to Active OLT are offline. Currently, service is not down because Standby OLT provide the services.

Handling Process
1. Asked customer to check on the physical part such as fiber, splitter and PON port status.
2. From customer feedback, it seems fiber reading is in range of all fiber.
3. Check whether the PON port is shut down by someone else, and we requested customer to provide configuration file.
4. After checked on the configuration file, it seems ”xpon ont-whitelist gpon ” is enabled in the OLT which may cause ONT cannot online due to white list enabled and no any ONT in the white list.
5. When we disabled the xpon ont-whitelist gpon, all ONTs in the back online. (Note: as a default, the ont-whitelist gpon is disabled)
Check whether the PON port is shutdown by someone else
Root Cause
ONTs offline in OLT due to xpon ont-whitelist gpon is enabled. caused ONT cannot online due to white list enabled and no any ONT in the white list.
Solution
Disable the xpon ont-whitelist gpon
Suggestions
Check on the configuration and do not forget to save after made changes.