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vCloud Automation Center Disaster Recovery

Gary BlakeBy Gary Blake

Prior to the release of vCloud Automation Center (vCAC) v5.2 there was no awareness or understanding of vCenter Site Recovery Manager protecting virtual machines. However, with the introduction of vCAC v5.2, VMware now provides enhanced integration so vCAC can correctly discover the relationship between the primary and recovery virtual machines.

These enhancements consist of what may be considered minor modifications, but they are fundamental enough to ensure vCenter Site Recovery Manager (SRM) can be successfully implemented to deliver disaster recovery of virtual machines managed by vCAC.

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So What’s Changed?

When a virtual machine is protected by SRM a Managed Object Reference ID (or MoRefID) is created against the virtual machine record in the vCenter Server database.

Prior to SRM v5.5 a single virtual machine property was created on the placeholder virtual machine object in the recovery site vCenter Server database called “ManagedBy:SRM,placeholderVM,” but vCAC did not inspect this value, so it would attempt to add a second duplicate entry into its database. With the introduction of 5.2, when a data collection is run, vCAC now ignores virtual machines with this value set, thus avoiding the duplicate entry attempt.

In addition, SRM v5.5 introduced a second managed-by-property value that is placed on the virtual machine vCenter Server database record called “ManagedBy:SRM,testVM.” When a test recovery process is performed and data collection is run at the recovery site, vCAC inspects this value and ignores virtual machines with this set. This too avoids creating a duplicate entry in the vCAC database.

With the changes highlighted above, SRM v5.5 and later—and vCAC 5.2 and later—can now be implemented in tandem with full awareness of each other. However, one limitation still remains when moving a virtual machine into recovery or re-protect mode: vCAC does not properly recognize the move. To successfully perform these machine operations and continue managing the machine lifecycle, you must use the Change Reservation operation – which is still a manual task.

Introducing the CloudClient

In performing the investigation around the enhancements between SRM and vCAC just described, and on uncovering the need for the manual change of reservation, I spent some time with our Cloud Solution Engineering team discussing the need for finding a way to automate this step. They were already developing a tool called CloudClient, which is essentially a wrapper for our application programming interfaces that allows simple command line-driven steps to be performed, and suggested this could be developed to support this use case.

Conclusion

In order to achieve fully functioning integration between vCloud Automation Center (5.2 or later) and vCenter Site Recovery Manager, adhere to the following design decisions:

  • Configure vCloud Automation Center with endpoints for both the protected and recovery sites.
  • Perform a manual/automatic change reservation following a vCenter Site Recovery Manager planned for disaster migration.

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Frequently Asked Questions

Q. When I fail over my virtual machines from the protected site to the recovery site, what happens if I request the built-in vCAC machine operations?

A. Once you have performed a Planned Migration or a Disaster Recovery process, as long as you have changed the reservation within the vCAC Admin UI for the virtual machine, machine operations will be performed in the normal way on the recovered virtual machine.

Q. What happens if I do not perform the Change Reservation step to a virtual machine once I’ve completed a Planned Migration or Disaster Recovery processand I then attempt to perform the built-in vCAC machine operations on the virtual machine?

A. Depending on which tasks you perform, some things are blocked by vCAC, and you see an error message in the log such as “The method is disabled by ‘com.vmware.vcDR’” and some actions look like they are being processed, but nothing happens. There are also a few actions that are processed regardless of the virtual machine failure scenario; these are Change Lease and Expiration Reminder.

Q. What happens if I perform a re-provision action on a virtual machine that is currently in a Planned Migration or Disaster Recovery state?

A. vCAC will re-provision the virtual machine in the normal manner, where the hostname and IP address (if assigned through vCAC) will be maintained. However, the SRM recovery plan will now fail if you attempt to re-protect the virtual machine back to the protected site as the original object being managed is replaced. It’s recommended that—for blueprints where SRM protection is a requirement—you disable the ‘Re-provision’ machine operation.


Gary Blake is a VMware Staff Solutions Architect & CTO Ambassador