Zyxel OLT2412 [301/326] Checking service related settings on the olt

Chapter 45 Troubleshooting

OLT2412 User’s Guide

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Check all ONU/ONT states in the same fiber network. If only one ONU/ONT can register but not the

others, this ONU/ONT may be malfunctioning.

Try to disconnect the ONT/ONU and test the OLT’s receiving optical power. If there is some power,

there might be some other devices mistakenly connected in the ODN, for example, a PON-enabled

switch. You may need to check each connected ONT/ONU to find the problematic one.

Change to a new transceiver, change the GPON card, or just try connecting the ONT to a different

GPON port to see if it works.

Checking Service Related Settings on the OLT.

Check if the ONT’s or ONU’s settings are correct and match the settings on the OLT. For example,

the VLAN settings should be properly configured on the OLT’s uplink ports, Gigabit Ethernet ports,

GPON port, and ONT/ONU port.

Check if the related QinQ (or VLAN stacking) settings are correct. For example, an access port has

some restrictions for VLAN translation.

Check if IPTV service is running properly and you can access the Internet successfully.

Check if the transmitting data rates are normal on the OLT uplink ports, GPON ports, the connected

ONT/ONU ports, and the ONT/ONU user ports. From the output traffic statistics, you can see if the

traffic amounts are normal. If too many packets were dropped related to a certain GPON port and

the ONT/ONU is functioning normally, check the settings on the port. If there were too many

broadcast and multicast packets, check the VLAN settings for transmitting the upstream and

downstream services and make sure QinQ is enabled.

Use the show mac address all command to check the MAC table on the OLT to see if the MAC

addresses of the ONTs/ONUs and the uplink gateway device were learned on the corresponding

ports.

45.1 Rogue ONT Troubleshooting

The OLT controls and arranges different time slots for each ONT/ONU in the same fiber network for

transmitting upstream traffic. A rogue ONT/ONU means the ONT transmits traffic during a time

allocated to another ONT/ONU. One rogue ONT/ONU may cause the rest of the ONTs/ONUs

connected to the same PON port to fail to transmit traffic. You can use the test interface olt

rogue pon-<slot>-<port> command to discover rogue ONTs, especially when you receive reports

from multiple ONTs/ONUs not being able to transmit traffic. This example performs a rogue ONT

discovery up to 1000 milliseconds (around 16.67 seconds). The OLT adds two normal ONTs/ONUs

back with serial numbers 414C434C25004992 and 5A59584500000011. They were disconnected