Hello,
The possible causes are as follows:
1. The optical channel quality is poor.
2. The ONT does not function properly.
3. A rogue ONU sending weak optical signals is under the PON port.
Procedure:
1. Run the display port ont-register-info command to query the ONT that is connected to the port and fails in ranging.
2. Run the display port info command to query the minimum and maximum logical distances on the port. Check whether the ONT that fails in ranging is within the ranging distance configured at the central office (CO) end.
1) If yes, go to 4.
2) If not, go to 3.
3. Run the port range command to configure the compensation distance for ranging on the gigabit passive optical network (GPON) port so that the ONT that fails in ranging is within the ranging distance configured at the CO end. Check whether the clear alarm is generated.
1) If yes, go to 9.
2) If not, go to 4.
4. Run the anti-rogueont manual-check portid detail command to query whether a rogue ONU is under a GPON port.
1) If yes, go to 9
2) If not, go to 5
5. Check whether the optical fiber is properly connected.
1) If the optical fiber is loose or disconnected, reconnect the optical fiber properly. Then, go to 7.
2) If the optical fiber is aged, bent, or damaged, replace the optical fiber. Then, go to 7.
3) If the connector of the optical fiber is dirty, clean the connector of the optical fiber. Then, go to 7.
4) If the optical fiber is properly connected, go to 6.
6. Reset or replace the ONT.
7. Check whether the clear alarm is generated.
1) If yes, go to 9.
2) If not, go to 8.
8. Contact Huawei for technical support.
9. End.
Thanks!
