Networking condition: The MA5600T is connected to the MA5652G to form the FTTB application scenario. DHCP option82 is enabled on both the MA5600T and MA5652G. A VDSL user connected to the MA5652G fails to obtain an IP address in the DHCP mode.
On the basis of cause analysis, the following operations are performed:
1. Run the display ont info command. It is found that the ONT works in the normal state.
2. Check the service configuration of the ONT. No error, however, is found.
3. Connect the HG850a to the MA5652G on the same PON port, and configure the traffic stream on the same VLAN. It is found that the PC connected to the HG850a can obtain an IP address normally in the DHCP mode.
4. Check the configuration again. It is found that the DHCP option82 function is enabled on both the OLT and the MA5652G. After disabling the DHCP option82 function on the OLT or MA5652G, the service returns to normal.
Finally, according to the comments from a user, enable the DHCP option82 function on the MA5652G, so that this function can be transparently transmitted on the OLT.
The causes of XPON service failure are as follows:
1. The ont-profile configuration is inconsistent with the ONT capability configuration, resulting in the abnormal configuration state after the ONT is online.
2. The traffic stream configuration is wrong.
3. The upper layer network incurs a fault or configuration problem.
The DHCP option82 function can only be configured in the transparent transmission mode on the OLT when this function is enabled on the MDU; otherwise, the OLT discards the packets with the DHCP option82 information.