Hello,
Today I would like to share with you the OLT optical module problem causes the multicast program to be unstable.
1. Fault description
Network structure: TV -> STB -> ONU -> OLT -> Switch -> BRAS -> Multicast source
When a user orders a multicast program, the program stream appears to be stuck.
2. Fault handling process:
Confirm with the user that the multicast source program is working properly.
This phenomenon still occurs when replacing another set-top box, and troubleshoot the set-top box.
Use the dis port stat command to view the parameter settings and status of all ports on each service board, and they are all normal.
Use the display traffic table ip command to view the ONU's rate limit bandwidth for the downstream multicast VLAN, reference template No. 10, and the CIR is 3M.
Run the display port statistics command to view the performance parameters of the PON port. There is no packet loss or error packet on the PON port.
Configure the Layer 3 address for the user VLAN on the ONU, and the ONU and PC will ping each other without packet loss.
Run the display port statistics command to view the performance parameters of the OLT upstream port, and there is no error packet loss.
Configure the Layer 3 address for the user VLAN on the OLT side, and ping each other with the PC without packet loss.
Through the above software check and port check, the OLT to the user's computer checks and judges that there is no problem, and it is suspected that the fault is in the upper equipment.
The gateway address of the OLT device PING BRAS has packet loss, which proves that the device on the OLT upstream port to the BRAS segment is faulty.
Replace the fiber. Found that there is still packet loss.
Replace the OLT optical module. It was found that there was no packet loss, and the multicast program card phenomenon also disappeared. Therefore, the fault of the multicast card is located due to the optical module problem of the upper-layer switch equipment.
3. Review of the problem:
There are many reasons for the unsmoothness of multicast program on-demand. It is necessary to sort out as many fault causes as possible. Starting from the user side, check and eliminate step by step, which can be replacement method, elimination method, loopback test and other methods.
You are welcome to leave a message and exchange in the comment area. Thank you!
