How to Perform a VM Failover in SynetoOS 6.1

Written By Sebastian Sime (Super Administrator)

Updated at September 28th, 2026

Table of Contents

Perform Failover Cancel Failover Recent Failovers

→ Applies to: SynetoOS 6.1.0 and above

A Failover is the switching mechanism that transfers operations from a failed primary component to a redundant backup component during an outage. By design, when a VM failover is performed from one site to another and the VM is registered at the destination, it remains visible at the source site in an unregistered state. This is expected behavior and it persists until a replication relationship is established from the destination site back to the source. Once reverse replication is configured and the destination site starts replicating the VM back to the source, the original VM entry is automatically removed from the source site and reappears under the Replicas section.

A Permanent Failover is the deliberate action of making the destination the new primary site for good, you're committing to it as the ongoing source of truth, rather than treating it as a temporary stand-in while the original source recovers. Once performed, the temporary safety block on reverse replication no longer applies, since you're no longer planning to fail back to the original source.

IMPORTANT
As long as the failover is active and a permanent failover has not been performed, replication tasks from the source to the destination remain automatically blocked. Incoming replications are denied to prevent overwriting data on the destination. Only once the permanent failover has been performed is this block lifted, allowing reverse replication to be configured normally.

Perform Failover

Step 1. Login to SynetoOS GUI

https://<your_ip_address_or_hostname>

Step 2. Add Replication Target ("How to Manage Replication Targets in SynetoOS 6")

IMPORTANT
Configure all nodes as mutual replication targets to establish bidirectional replication across the entire cluster.
This creates a full-mesh topology in which every node both sends and receives replicas to and from all other nodes. If replication targets are already configured, skip this step.

Step 3. Configure a SLA policy to replicate (“How to Configure a SLA policy to Replicate on a Secondary System in SynetoOS 6”)

If the SLA policy is already configured, this step is not required

Step 4. Protect VM ("How to Protect a VM in SynetoOS 6")

If the VM is already protected, this step is not required
If the VM is not yet protected, it is necessary to wait until the first replica is completed. The initial backup will be a full backup of the entire VM

Step 5. From the Protection menu, click on Replicas

Step 6. Select the VM you want to fail over from the Replicas list, then click Failover

Step 7. Fill in the required fields and click on Next

IMPORTANT
The VM can be registered at the destination either during the failover process or manually at a later stage.

Step 8. Select the SLA policy and click on Next

IMPORTANT
A protection policy from the replication target can be selected at this stage or configured at a later time.
The choice of whether to assign an SLA policy at this stage determines the resulting state of the original VM on the source site.

Scenario 1: SLA Policy Assigned If an SLA policy is assigned during this process, the first replication to the destination site will automatically convert the original VM on the source site into a replica.

Scenario 2: No SLA Policy Assigned If no SLA policy is assigned, the VM will remain in an unregistered state on the source site until a replication relationship from the destination site back to the source is established.

Step 9. Check the entire configuration and click on Failover