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Initiating a Chassis Cluster Manual Redundancy Group Failover

You can initiate a failover manually with the request command. A manual failover bumps up the priority of the redundancy group for that member to 255.

Before you begin, complete the following tasks:

Caution: Be cautious and judicious in your use of redundancy group 0 manual failovers. A redundancy group 0 failover implies a Routing Engine (RE) failover, in which case all processes running on the primary node are killed and then spawned on the new master Routing Engine (RE). This failover could result in loss of state, such as routing state, and degrade performance by introducing system churn.

Note: For redundancy groups x (redundancy groups numbered 1 through 128), it is possible to do a manual failover on a node that has 0 priority . We recommend that you check the redundancy group node priorities before doing the manual failover.

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

{primary:node0}
user@host> show chassis cluster status redundancy-group 0
Cluster ID: 9
Node                  Priority          Status    Preempt  Manual failover

Redundancy group: 0 , Failover count: 1
    node0                   254         primary        no       no
    node1                   1           secondary      no       no

Output to this command indicates that node 0 is primary.

Use the request command to trigger a failover and make node 1 primary:

{primary:node0}
user@host> request chassis cluster failover redundancy-group 0 node 1
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Initiated manual failover for redundancy group 0

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

{secondary-hold:node0}
user@host> show chassis cluster status redundancy-group 0
Cluster ID: 9
Node                  Priority          Status    Preempt  Manual failover

Redundancy group: 0 , Failover count: 2
    node0                   254         secondary-hold no       yes
    node1                   255         primary        no       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.

You can reset the failover for redundancy groups by using the request command. This change is propagated across the cluster.

{secondary-hold:node0}
user@host> request chassis cluster failover reset redundancy-group 0
node0:
--------------------------------------------------------------------------
No reset required for redundancy group 0.

node1:
--------------------------------------------------------------------------
Successfully reset manual failover for redundancy group 0

You cannot trigger a back-to-back failover until the 5-minute interval expires.

{secondary-hold:node0}
user@host> 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.

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

{secondary-hold:node0}
user@host> show chassis cluster status redundancy-group 0
Cluster ID: 9
Node                  Priority          Status    Preempt  Manual failover

Redundancy group: 0 , Failover count: 2
    node0                   254         secondary-hold no       no
    node1                   1           primary        no       no

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

After doing a manual failover, you must 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).

 

Related Documentation

 

Modified: 2016-07-21

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