VMware vSphere does not support snapshots of virtual machines with the VMware Fault Tolerance feature enabled. Therefore, Agent for ESX(i) does not back up these machines and you cannot select them for backup under Virtual machines. If you include a group containing a fault tolerant machine in a backup plan, this machine will be automatically excluded.
To back up a fault tolerant virtual machine, do one of the following:
Note that you should "turn off" rather than "disable" it; otherwise, a snapshot will not be created. You can turn Fault Tolerance off and on when required using vSphere scripts. Normally this works, but unnecessary actions (such as removing or creating the secondary virtual machine) take time and resources. Also, the machine reliability is reduced during the backup.
An Acronis Backup & Recovery 11 Virtual Edition license assigned to the host enables you to install agents in an unlimited number of guest systems.
For more information about how to install the agent, see the installation documentation.
After you install the agent and add the machine to the management server, the machine appears under Machines with agents in the All machines with agents group. When creating a backup plan, select the machine here rather than under Virtual machines. Or, you can connect the console to the machine directly as to a physical machine.