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Failing over agentless Hyper-V jobs

When a failover condition has been met, failover will be triggered automatically if you disabled the wait for user option during your failover configuration. If the wait for user before failover option is enabled, you will be notified in the console when a failover condition has been met. At that time, you will need to trigger it manually from the console when you are ready.

1. On the Manage Jobs page, highlight the job that you want to failover and click Failover or Cutover in the toolbar.
2. Select the type of failover to perform.
• Failover to live data—Select this option to initiate a full, live failover using the current data on the target. This option will shutdown the source machine (if it is online), stop the protection job, and start the replica virtual machine on the target with full network connectivity.
• Perform test failover—Select this option to perform a test failover using the current data on the target. This option will leave the source machine online, stop the protection job, and start the replica virtual machine on the target without network connectivity.
• Failover to a snapshot—Select this option to initiate a full, live failover without using the current data on the target. Instead, select a snapshot and the data on the target will be reverted to that snapshot. This option will not be available if there are no snapshots on the target or if the target does not support snapshots. This option is also not applicable to clustered environments. To help you understand what snapshots are available, the Type indicates the kind of snapshot.

  • Scheduled—This snapshot was taken as part of a periodic snapshot. 

  • Deferred—This snapshot was taken as part of a periodic snapshot, although it did not occur at the specified interval because the job between the source and target was not in a good state.

  • Manual—This snapshot was taken manually by a user.

3. Select how you want to handle the data in the target queue. You may want to check the amount of data in queue on the target by reviewing the Statistics or Performance Monitor.
• Apply data in target queues before failover or cutover—All of the data in the target queue will be applied before failover begins. The advantage to this option is that all of the data that the target has received will be applied before failover begins. The disadvantage to this option is depending on the amount of data in queue, the amount of time to apply all of the data could be lengthy.
• Discard data in the target queues and failover or cutover immediately—All of the data in the target queue will be discarded and failover will begin immediately. The advantage to this option is that failover will occur immediately. The disadvantage is that any data in the target queue will be lost.
• Revert to last good snapshot if target data state is bad—If the target data is in a bad state, Double-Take will automatically revert to the last good Double-Take snapshot before failover begins. If the target data is in a good state, Double-Take will not revert the target data. Instead, Double-Take will apply the data in the target queue and then failover. The advantage to this option is that good data on the target is guaranteed to be used. The disadvantage is that if the target data state is bad, you will lose any data between the last good snapshot and the failure.

4. When you are ready to begin failover, click Failover.

   Depending on your replica configuration, you may have to reboot your replica after failover. You will be prompted to reboot if it is necessary.

   In a cluster configuration, if you move the shared storage ownership on the original source cluster or change the drive letter after failover, you will be unable to reverse your protection. Keep the source cluster configuration the same in order to allow proper reversing of protection.

    

5. If desired, you can undo your live or test failover by selecting Undo Failover or Cutover in the toolbar. In either case, the replica virtual machine on the target will be shut down and the protection job will be restarted performing a file differences mirror. The one difference when undoing a live failover is the virtual machine on the source will be started. This step is not needed when undoing a test failover, because the virtual machine on the source is not shut down during a test failover. In both cases, all changes made on the replica virtual machine on the target will be lost. If you do not want to lose data changes made on the replica virtual machine on the target, see Reversing agentless Hyper-V jobs

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