After expansion reconstruction, the SLQ1 of the OSN 1500 interconnects with a router of Company C through an optical port. The networking mode is 1+1 MS chain. One end of the chain is the 2M service and the other end is 155M optical port.
The tributary path of the 2M service side reports the LP_RDI alarm.
1. Refer to related documents. VC4 services were configured on the interconnected port of the SLQ1 on the OSN 1500, and this port is configured with VC12 services now. That is, VC12 services are added after VC4 services are deleted on the same port.
2. After the lower order VC12 service of the SLQ1 is configured, query the overhead mode of the service on the 155M optical port. The overhead processing mode is "pass-through". Change the mode to "terminate". Then, the LP_RDI alarm of the remote 2M service disappears and services work normally.
For lower order services, the higher order overhead of the line board must be in terminated mode. If the higher order overhead of the line board is in the pass-through mode, services are interrupted. Thus, when the higher order service is changed to lower order service, check whether the overhead processing mode is correct.
See also case in chinese:SC0000168636