Failover is when Veeam Backup & Replication switches processes from the source VM in the production site to its replica in the disaster recovery site. During failover, Veeam Backup & Replication recovers the replica to the required restore point and shifts all I/O processes from the source VM to its replica. As a result, you have a fully functional VM within a couple of seconds, and your users can access services and applications with minimum disruption.
You can fail over to replicas not only when a disaster strikes the production site, but also to test replicas for recoverability. If the source VMs and VM replicas are located in the same network, consider temporary disconnecting the source VMs from the network to avoid IP address or machine name conflicts.
How Failover Works
The failover operation is performed in the following way:
- Veeam Backup & Replication puts all replication activities on hold.
- The state of the replica is changed from Ready to Failover.
- Veeam Backup & Replication recovers a replica to the required restore point.
- Veeam Backup & Replication powers on the replica.
If you perform failover for testing purposes, and the source VM still exists and is running, the source VM remains powered on.
- All changes made to the replica disks while the replica is running in the Failover state are written to the protective virtual disks (<disk_name>-interim.vmdk files).
Failover is an intermediate step that needs to be finalized. You can perform the following operations: