TDM Switch(ZTE) --> UA5000 --> MA5680T --> OT928G --> ONU60A --> Phone
Connect UA5000 and ONU60A directly, service is OK.
Add MA5680T and OT928G, MA5680T and OT928G port status is normal, but E1 link in ONU60A can not up, downstream port in UA5000 is fault, so service is no OK.
1. Check Physical Connection --> t's OK.
2. Check Software commissioning:
UA5000 --> ONU60A directly is OK, so the configuration is OK;
MA5680T --> OT928G configuration follows the manual, can not find out the errors.
3. Loopback Test: (the details in attachment)
loopback UA5000 and ONU60A, downstream port and E1 link is normal;
loopback MA5680T+OT928G, port status is fault;
Step 1 shows that physical connection is OK ;
Step 2 shows MA5680T+OT928G has a little problem, maybe the configuration
Step 3 shows MA5680T+OT928G has problem
Step 4 Confirm with HQ, then we know we should change DBA bandwidth to 4416kbps for OT928G, and different ONT has different DBA bandwidth; after changing it to 4416kbps, the service is normal;
1. physical connection
2. software configuration
Manual is just for reference.
Add the DBA bandwidth setting requirement in the manual, or we don't know we should change DBA bandwidth if we just follow the existing manual.