What can I do if the GPON ONU cannot Connect to the OLT

 OLT

 A single ONU or some ONUs connected to an OLT fail to go online.

• The SN or password configured on the OLT is different from the actual SN or password of the ONU; hence, the ONU fails to pass authentication and go online.

• The actual distance between the ONU and OLT exceeds the ranging compensation distance configured on the OLT.

• The OLT deactivates the ONU. 
  
  
  
  

 OLT

 All the ONUs connected to a PON port of an OLT fail to go online.

• The laser on the PON port is disabled.

• The pluggable optical module of the PON is faulty.

• The PON port is faulty.
  
  
  
  

 OLT

 All the ONUs connected to a board of an OLT fail to go online.

 The board or the slot is faulty.

 ODN

The PON port reports alarms described in ODN-Related Alarms, including:
0x2e11a001 The feeder fiber is broken or OLT can not receive any expected
optical signals(LOS)
0x2e112007 The distribute fiber is broken or the OLT cannot receive expected
optical signals from the ONT(LOSi/LOBi)

ODN failures are generally caused by large reflection and attenuation caused by improper optical components, design, or construction. For details, see Common ODN Faults.

• If a single ONU or multiple ONUs fail to go online, the branch fiber and the optical component may have faults.

• If all ONUs fail to go online, the backbone fiber and the optical component may have faults.
  
  
  
  

 ONU

A single ONU or some ONUs connected to an OLT fail to go online.

•  The ONU is not powered on.

• The information (including SN and password) for ONU authentication conflicts; hence, the later power-on ONU fails to go online.

• A rogue ONU exists on the network and affects other ONUs.

• The ONU hardware is faulty.

• The optical module of the ONU is faulty.

• The patch cord of the ONU is broken or bent excessively.

• The ONU is incorrectly connected to another PON port.