One of our customer reported that they are having an MSP ring of 11 nodes, when one node (NE-1965 in attached fig) goes power off, the VC12 level services are interrupted at the adjacent site (NE-1966).All the other services at other nodes are protected as MSP Switching occurs.All the ring contains the OSN3500 nodes with NeSoft as 188.8.131.52P01.
Following things can be verified.
1.Check the MSP configuration on all the nodes in the Ring.
2.Check whether the MSP protocol started when the issue occurs.
3.Check the configurations of the specific interrupted services as consistent in case of MSP.
In this case, first two things was verified and found OK, when the service configuration of interrupted services was checked, it was found configured on the
inconsisten VC12's that caused the service interruption in case of MSP Switch.
The MSP configurations on all the nodes in the ring were verified and found OK.The MSP switching was tested and its protocol status was also checked and found
OK.From the detailed analysis of the specifically interrupted services it was found that these services are configured in inconsistent VC12's at the node that goes
Power OFF (NE-1965).The inconsistent VC12's configuration in also identified in the attached fig.
It is the feature of the Ring MSP that it can protect only the services configured in the consistent VC12's or VC4's.
The MSP configurations on all the nodes in the Ring MSP should be same.
The services should be configured on consistent VC12's or VC4's in the Ring MSP.