The time required to failover depends on how long it takes to manually promote the replica and redirect traffic. The average time ranges between 2-10 minutes.
Promoting a replica does not automatically set up replication for existing appliances. After promoting a replica, if desired, you can set up replication from the new primary to existing appliances and the previous primary.
- To allow replication to finish before you switch appliances, put the primary appliance into maintenance mode:
- To use the management console, see "Enabling and scheduling maintenance mode"
- You can also use the
ghe-maintenance -scommand.$ ghe-maintenance -s
- When the number of active Git operations reaches zero, wait 30 seconds.
- To verify all replication channels report
OK, use theghe-repl-status -vvcommand.$ ghe-repl-status -vv - To stop replication and promote the replica appliance to primary status, use the
ghe-repl-promotecommand. This will also automatically put the primary node in maintenance node if it’s reachable.$ ghe-repl-promote - Update the DNS record to point to the IP address of the replica. Traffic is directed to the replica after the TTL period elapses. If you are using a load balancer, ensure it is configured to send traffic to the replica.
- Notify users that they can resume normal operations.
- If desired, set up replication from the new primary to existing appliances and the previous primary. For more information, see "About high availability configuration."
- Appliances you do not intend to setup replication to that were part of the high availability configuration prior the failover, need to be removed from the high availability configuration by UUID.
- On the former appliances, get their UUID via
cat /data/user/common/uuid.$ cat /data/user/common/uuid - On the new primary, remove the UUIDs using
ghe-repl-teardown. Please replaceUUIDwith a UUID you retrieved in the previous step.$ ghe-repl-teardown -u UUID
- On the former appliances, get their UUID via