Returning to production after a cloud-hosted disaster recovery scenario

Question

How do I fail back to a production environment when running a virtualized server in the Datto Cloud?

Environment

  • Datto SIRIS
  • Datto ALTO
  • Datto Image

Answer

Before you start

This procedure presumes you have been running a VM in the Cloud for some time and have been taking regular ZFS snapshots. Contact Datto Technical Support to verify snapshots have been taken.

Procedure

Take a snapshot and send the data

  1. Power down the VM.
  2. Datto Technical support will take a snapshot of the powered-off VM.
  3. The Datto technician will set up a reverse send to deliver the snapshot to the local Datto appliance. If the snapshot is too large to download via reverse send, the technician will deliver the data via reverse RoundTrip.
  4. Power up the VM. It can be used during the duration of the reverse send or reverse RoundTrip process.

Restore the data on the local machine

  • If restoring back to a physical machine, use the BMR (bare metal restore) method. If the agent is very large, Datto Technical Support can virtualize a rescue agent with a rescue agent and continuous mirroring, allowing the VM to keep running and restore live changes to the new machine.
  • If restoring to a virtual environment, you can choose a VMDK or VHD export. If the agent is very large, Datto Technical Support can virtualize it via hypervisor and use vMotion to pull the live VM into your environment.

Restore the changes made on the running VM during the sync process

This process is like the send process above, with a much shorter window.

  1. Power down the offsite VM.
  2. Datto Technical Support will take a snapshot of the powered-off VM containing the changes from the previous snapshot.
  3. Datto Technical Support will send the changed data to the local Datto device via reverse send.
  4. The snapshot will be presented as an iSCSI file restore that will be pulled over using Robocopy (to maintain needed Windows permissions).

The restoration process is now complete, and the machine is production-ready.

Notes on the reverse send process

NOTE  The sync portion of the reverse send process is the most time-intensive part of the restore.

The reverse send process has 3 parts:

  1. Compressing the point for sending: This compression lessens the download time to the local device. Compression time depends on the compression ratio for the desired server and the amount of data being compressed.
  2. Sending and receiving data: This is the straightforward downloading of the data to the local Datto device.
  3. Unpacking the data: When the local Datto device receives the send file, it will decompress the data. Datto Technical Support will then make the data accessible for restoration.

Restoring in a full site-down situation

If the organization site is down and the local Datto device is destroyed, Datto will replace the device, seed it with the required offsite data, then follow the procedure above to make the information on the offsite VM available for restoration.

Additional resources