Juniper SRX: Initiating a Chassis Cluster “Manual Redundancy Group Failover”.

It is possible to initiate a failover state manually (from the CLI) with the request command.

A manual failover bumps up the priority of the redundancy group for the specified member to 255, triggering its state.

Use the show command to display the status of nodes in the cluster:

{primary:node0}
twister@gw-srx-01> show chassis cluster status redundancy-group 0
Cluster ID: 1
 
Node                  Priority          Status    Preempt   Manual failover
Redundancy group: 0 , Failover count: 0
    node0                   100         primary        yes       no
    node1                   1           secondary      yes       no

Output to this command indicates that node 0 is in primary state.

By using the request command it is possible to trigger a failover and make node 1 primary:

{primary:node0}
twister@gw-srx-01> request chassis cluster failover redundancy-group 0 node 1
 
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Initiated manual failover for redundancy group 0

with the show command it is possible to display the new status of nodes in the cluster:

{secondary-hold:node0}
twister@gw-srx-01> show chassis cluster status redundancy-group 0
 
Cluster ID: 1
Node                  Priority          Status    Preempt  Manual failover
 
Redundancy group: 0 , Failover count: 1
    node0                   100         secondary-hold yes      yes
    node1                   255         primary        yes      yes

Output to this command shows that node 1 is now primary and node 0 is in the secondary-hold state.
After 5 minutes, node 0 will transition to the secondary state.

It is possible to reset the failover for redundancy groups by using the request command.
This change is propagated across the cluster.

{secondary-hold:node0}
twister@gw-srx-01> request chassis cluster failover reset redundancy-group 0 node 0
 
node0:
--------------------------------------------------------------------------
No reset required for redundancy group 0.
 
node1:
--------------------------------------------------------------------------
Successfully reset manual failover for redundancy group 0

It is not possible to trigger a back-to-back failover until the 5-minute interval expires.

{secondary-hold:node0}
twister@gw-srx-01> request chassis cluster failover redundancy-group 0 node 0
 
node0:
--------------------------------------------------------------------------
Manual failover is not permitted as redundancy-group 0 on node0 is in secondary-hold state.

Using the show command it is possible to display the new status of nodes in the cluster:

{secondary-hold:node0}
twister@gw-srx-01> show chassis cluster status redundancy-group 0
 
Cluster ID: 1
Node                  Priority          Status    Preempt  Manual failover
 
Redundancy group: 0 , Failover count: 2
    node0                   100         secondary-hold yes      no
    node1                   1           primary        yes      no

Output to this command shows that a back-to-back failover has not occurred for either node.

After doing a manual failover, it is mandatory to issue the reset failover command before requesting another failover.

When the primary node fails and comes back up, election of the primary node is done based on regular criteria (priority and preempt).


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