You can failover to a GitHub Enterprise replica appliance using the command-line for maintenance and testing, or if the primary appliance fails.

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.

  1. To allow a replication to finish before you switch appliances, put the primary appliance in maintenance mode.
  2. When the number of active Git operations reaches zero, wait 30 seconds.
  3. Use the ghe-repl-status -vv command to verify all replication channels report OK:

    ghe-repl-status -vv
    
  4. Use the ghe-repl-promote command to stop replication and promote the replica appliance to primary status:

    ghe-repl-promote
    
  5. 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.

  6. Notify users that they can resume normal operations.
  7. If desired, set up replication from the new primary to existing appliances and the previous primary. For more information, see "About High Availability configuration."

Further reading