Acronis vmProtect has two ways of recovering virtual machines: to the original VM or to a new one. If recovery is performed to the original location, Acronis vmProtect tries to locate the source VM using its GUID and if the VM is missing a new VM will be created.
Recovering to the original VM
In case the original VM exists the software uses the following algorithm:
- When the recovery operation is started Acronis vmProtect powers off and creates a quiescied snapshot of the target VM using VMware API. This technical snapshot is required to be able to rollback in case the recovery operation fails.
- After the snapshot is created Acronis vmProtect mounts virtual disks to the Virtual Appliance and recovers data to the existing disks. If Windows Agent is used or the Hot-Add functionality is not available, recovery is performed via network directly to the target VM.
- After data is recovered the software disconnects virtual disks from the Virtual Appliance and sends command to remove the technical snapshot created in the first step.
- And only after all these steps are performed the target VM is started.
If restore fails the software will rollback using to the snapshot created in the first step.
Recovering to a new VM
If the original VM is missing or the option to recover to a new VM is chosen the following algorithm is used:
- Acronis vmProtect sends the command to create a virtual machine on the VMware ESXi host where the recovery is performed
- After the VM is created Acronis vmProtect mounts the virtual disks to the VA and recovers the data to existing disks. If WA is used or the Hot-Add functionality is not available then recovery is performed via the network directly to target VM.
- After recovery is finished, the disks are disconnected and the VM is started.
The difference between these algorithms is that the snapshot creation is not required in case if new VM is created. Besides that if recovery is performed to existing VM then the vmFlashBack feature can be used.