This Article explains the steps to check the graceful switchover status of standby routing engine, before toggling the primary role between the Routing engines (RE).

{master}

Lab_re0> request chassis routing-engine master switch    

Toggle mastership between routing engines ? [yes,no] (no) yes

Resolving mastership...

Complete. The other routing engine becomes the master.

Sometimes, after performing the mastership switchover this leads to PFE's getting restarted leading into impact.

The impact would be seen if the backup routing engine is not ready for the graceful switchover. Below mentioned steps can be performed to avoid any issues.

In order to avoid any unforeseen issues, before performing the mastership switchover, we need to check if the Backup RE is ready for the switchover. Following steps can be taken :

a. Always use the show system switchover command on the backup Routing Engine to determine if the backup is ready to take over as the primary Routing Engine.

{backup}

Lab_re1> show system switchover 

Graceful switchover: On

Configuration database: Ready

Kernel database: Ready

Switchover Status: Ready

Display whether graceful Routing Engine switchover is configured, the state of the kernel replication (ready or synchronizing), any replication errors, and whether the primary and standby Routing Engines are using compatible versions of the kernel database.

b. Check graceful switchover status of the backup Routing engine, by using below command on Primary RE.

{master}

Lab_re0> request chassis routing-engine master switch check 

Switchover Ready

If the router or switch displays a warning message similar to “Standby Routing Engine is not ready for graceful switchover. Packet Forwarding Engines that are not ready for graceful switchover might be reset,” do not attempt switchover. If you choose to proceed with switchover, only the Packet Forwarding Engines that were not ready for graceful switchover are reset.

{master}

Lab_re0> request chassis routing-engine master switch check

warning: Standby Routing Engine is not ready for graceful switchover.

Packet Forwarding Engines that are not ready for graceful switchover might be reset.

Standby Routing Engine is not ready for graceful switchover.

Its recommend that you wait until the warning no longer appears and then proceed with the switchover.
 

c. Before performing the mastership switchover, check the Database and protocol synchronization is completed between the RE’s with NSR enabled.

Below commands will help to check the status of the synchronization:

{master}
LAB_re0> show task replication
         Stateful Replication: Enabled
         RE mode: Master

     Protocol                Synchronization Status
     OSPF                    Complete
     BGP                     Complete
     IS-IS                   Complete
     LDP                     Complete
     PIM                     Complete


{backup}
LAB_re1> show database-replication summary

General:
    Graceful Restart           Enabled
    Mastership                 Standby
    Connection                 Up
    Database                   Synchronized
    Message Queue              Ready
 

For further details, refer below mentioned Techpub's :

https://www.juniper.net/documentation/us/en/software/junos/high-availability/topics/ref/command/show-system-switchover.html
https://www.juniper.net/documentation/us/en/software/junos/high-availability/topics/ref/command/request-chassis-routing-engine-master.html
https://www.juniper.net/documentation/us/en/software/junos/high-availability/topics/ref/command/show-task-replication.html

2023-09-26 : Initial Version