Core resiliency: Control plane resiliency enhancements

Control plane resiliency is improved with the following enhancements:

• The primary and standby Routing Engines exchange detailed information about session database replication. This exchange enables the Routing Engines to better determine whether the replication is correct.
• You can configure the router to detect shared memory corruption and to automatically recover by rebooting the primary or standby Routing Engine, or both. In earlier releases, a manual reboot is required to clear the corrupted shared memory; otherwise, it remains corrupted, causing processes that share the memory to generate core errors.
• You can monitor Routing Engine resiliency with the show system subscriber-management resiliency command. The summary version indicates whether the system is functioning normally or an unexpected condition exists. The detail and extensive versions provide detailed information about the shared memory per Routing Engine.