How Orchestrator Places VMs During Failback

To fail back VMs included in a replica plan to a new recovery location, Orchestrator uses the following algorithm:

  1. The solution looks through all hosts added to the location as compute resources to detect the first available host. This is the host where the first processed VM will be registered.
  2. Orchestrator applies the mapping specified in the network mapping table for the location to set the required network configuration of the recovered VM.

Orchestrator checks whether the network configuration of the detected host matches the required network configuration. If these configurations do not match, Orchestrator goes back to step 1.

  1. In the list of datastores connected to the host as storage resources, Orchestrator searches for the first datastore that both is available and has enough capacity. This is the datastore where files of the VM will be stored.

To calculate the datastore capacity and make sure that it has enough space to accommodate the recovered VM, Orchestrator uses the threshold that you specify when creating or configuring the location.

 

Note

The failure of steps 1–3 for a VM from a critical inventory group halts the plan in the following cases:

  • If none of the discovered hosts is available, or if none of the hosts has network configuration that matches the required network configuration of the recovered VM.
  • If none of the discovered datastores is available, or if none of the datastores meets the capacity requirements.

To learn how to work with HALTED replica plans, see Managing Halted Plans.

  1. When Orchestrator starts processing the next VM, the solution looks through all hosts added to the location as compute resources to detect the next available host:
  • If Orchestrator detects such a host, this is the host where the VM will be registered.
  • If there are no more available hosts, Orchestrator uses the host detected at step 1 to register the VM.

Then, Orchestrator goes through steps 2–3 to detect the target network and datastore for the VM.

  1. Orchestrator repeats step 4 for all other VMs included in the plan until all the VMs are recovered. The order in which the VMs are processed depends on the VM Recovery Options defined while configuring the plan.

If datastores added to the recovery location as storage resources breach the capacity threshold before all the VMs are recovered, the failure of this step for a VM from a critical inventory group halts the plan. To troubleshoot the issue, configure the location to add more datastores and try running the halted plan again. To learn how to work with HALTED replica plans, see Managing Halted Plans.