NE1, NE2, NE3, NE4, and NE5 form an MSP ring, and there is an STM-1 link between NE1 and NE3. An SNCP VC-4 service is created between NE1 and NE3. The working source of this VC-4 service is on the MSP working path, and the protection source is on the STM-1 link. SNCP delay time is 100ms. When a fiber break occurs for the first time (between NE1 and NE2), the MSP switches normally. When the fiber is cut for the second time in the MSP ring (between NE3 and NE5), the SNCP service is interrupted and no SNCP protection switching occurs.
What are the solutions?

When the EX2 board of the PTN equipment is connected to the STM-64 port, how should the working mode of the interface be set?

GR (Graceful Restart) is one of the key technologies to provide HA. GR can make the entire system uninterrupted in the event of a failure switch, and can realize rapid network convergence under normal conditions.

If there is a problem with the CORBA connection, it can be analyzed as follows: If it is not a problem on the U2000 side, you should find it from the upper-layer network management itself or the U2000 and the upper-layer network management together; the name and notification service cannot be started normally, you should check whether the corresponding port is occupied, or Try to use other ports; if U2000 fails to start, check whether the CORBA configuration files bundle.cfq and ems.cfq are correct

If the meter sending data frame rate is X and receiving data frame rate is Y, then the packet loss rate = (XY) /X*100%, usually the packet loss rate + throughput = 1