System failure workflow with an active-active link

The table below outlines what happens when one of the systems involved in an active/active link fails, where the system that fails is system A and the system that remains healthy is system B.

Step What you do What happens
System A Fails
1

On system B, fail over the link

If DNS failover is enabled, system B broadcasts new DNS configuration

2

If DNS failover is disabled, direct clients to write only to system B

 
System A comes back online
3

If system A has been rebuilt:

On system A, upload the replication SSL server certificate from system B

On system B, upload the replication SSL server certificate from system A

 
4

On system B, update the link configuration as needed

 
5

If the link is broken, on system B, send a request to restore the link

Replication link is recreated

6

On system B, fail back the link

System A and system B broadcast original DNS configurations; replication restarts in both directions on the link

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