Two Kinds of Disaster Recovery Pool
"Regional DR," covered here, creates replacement desktops from a recent backup image. This is used with persistent desktop pools, where preserving the individual users' customized desktops is important.
"PC DR," covered in Control: Disaster Recovery Pools (PC DR), gives users newly imaged replacement desktops. This is typically used for non-persistent pools, where users don't have a customized desktop.
Introduction
Workspot offers Regional Disaster Recovery (Regional DR) as an optional feature for Azure persistent desktop pools. Backups of the desktops in the pool are copied to an alternate Azure region. If the parent region becomes unavailable, the copies in the recovery region can be activated. These become available to your users instead of the original desktops and the users can continue working as before, using desktops that are only slightly out of date.
How Regional DR Works
The basic operation of Regional DR pools.
As shown in the diagram above, Regional DR transfers copies of desktop backups to the recovery region. These backups are bootable VMs When needed, the recovery copy of the desktop pool is activated and your users can continue working even though the parent region is down..
About the Recovery Region
The recovery region can be used for other purposes than recovery. It can be used in the same way as your existing region. For example, you can use it as the home region for new desktop pools.
Prerequisites
Regional DR requires some up-front configuration:
Regional DR is a licensed feature. Contact Workspot to enable it.
The Azure recovery region must be set up with subnets, RD gateways, etc. to be ready for Regional DR. Workspot will assist with this.
The recovery region will need access to the additional infrastructure that is used by the desktop pool, such as network file systems, AD servers, and so on. (If any of this resides solely in the parent region, you will want to replicate this as well.)
Regional DR is dependent upon Workspot’s desktop backup feature. This must be enabled. (See Desktop Backups.)
Only desktops and desktop templates using Workspot Agent 2.4.6 and up will function with Regional DR. VMs using earlier versions of Agent will copy to the remote region but cannot register with Workspot Control and thus are unusable.
Limitations
Regional DR is available only for persistent desktops.
Regional DR is not supported on GPU workstations.
Regional DR has not yet been tested across two Azure geographic clusters, such as when the parent region is in America and the recovery region is in Asia. Contact Workspot if your use case requires this.
Currently, the fallback templates used in the recovery region must be copied to the region manually. If the templates are updated, the updated templates must also be copied manually.
Currently, copying desktops back to the parent after Regional DR is deactivated must be done manually. Contact Workspot for more information.
Currently, some status messages in the Workspot Control UI are incorrect while Regional DR is being activated or deactivated. In particular, desktops may be shown in a Failed or Error state when they simply haven’t been fully activated yet.
Currently, the Workspot Client may give errors such as “No desktops are available in the pool” when the real issue is that the pool hasn’t been fully activated yet.
There will be a brief period after the Control R12.2 release where the Workspot Agent 2.4.6 has not yet been released. Acquire a pre-release version from Workspot if necessary.
Setting Up Regional DR
Once the recovery region itself has been set up with Workspot’s assistance and desktop backups and Regional DR have been activated, the process of enabling Regional DR on a specific desktop pool is as follows:
Create a backup policy that’s suited for your needs and licensing. For example, “daily backups with no retention backup.” (See Desktop Backups.)
This template can also be used as the fallback template for any desktops that lack a backup. Copy this template manually to the recovery region. Contact Workspot for assistance. If you update this template, the new template must also be copied.
Create a new desktop pool as described in the next step OR update an existing pool as follows:
Use “Update Image” to assign your new template to the pool. Any new desktops will use this template.
For assigned desktops running an old version of the Agent, install the Agent manually. (See “Download and Run the Agent Installer” in Workspot Agent 2.4 Installation for Templates.)
For unassigned desktops, edit the desktop pool and enable the “Auto Create on Desktop Delete” option, then delete the unassigned desktops. They will be recreated using the new template.
Create or edit your desktop pool to prepare it for Regional DR:
The pool must be a persistent desktop pool.
A backup policy must be assigned to the desktop pool.
We recommend testing with a small test pool before applying Regional DR to your large production pools.
Go to “Resources > VDI Pools.” On the “Action” menu for the parent pool, select “Configure Regional DR Pool.” Note the yellow warning banner.
Configure Regional DR Pool command.
Warning text.
Fill in the “Configure Regional DR Virtual Desktops” form as described below (See the diagram below the steps to see the fields that match the reference numbers):
Select the backup template to use in the recovery region. This template is used to image new desktops for any active desktops for which there are no recovery backups. Select a template that is actually available in the recovery region.
Recovery Region. Specify the recovery region. Only regions that have been set up by Workspot will be selectable.
Recovery Region DR Pool Name. Pick a unique name for the recovery pool. This will be used to identify the recovery pool in the Control UI.
Recovery Pool Display Name. Pick a name for the recovery pool to show to users in the Workspot Client. This should be close to the parent pool’s name but not identical to it. In the examples in this document, an “R” for “Recovery” has been appended to the parent pool’s display name.
Description. Provide an optional description for the recovery pool.
Desktop Name. Pick a base name for the pool VMs. Often this can be the same as the Recovery Region DR Pool Name and the Recovery Region Display Name if these are short enough. The name must be no more than fifteen character long, counting the hyphen and the number at the end.
Allow User to Reboot VM from Client. Set this to the same value used in the parent. Pool.
Route Through Gateway. Usually “always,” but should be set to be consistent with the gateway type that was set up for you in the recovery region (not the parent region).
Gateway Type. Set this to match the gateway type in the recovery region (not the parent region).
Gateway. Select the recovery region gateways.
Login Type. Set to match the selection used in the parent region.
Login Domain. Set to match the domain used in the parent region.
Configure Regional DR Virtual Desktops page.
Click “Save.”
If there were errors on the form, you will remain on the “Edit Regional DR Virtual Desktops” page. Scroll to the top to read the error message and correct the issue.
If Control detects no errors on the form, you are shown the “Manage Regional DR Virtual Desktop Pools” page and a green status message will report your success.
The recovery pool will be listed at the bottom section of the “Manage Virtual Desktop Pools” page under “Manage Regional DR Virtual Backup Pools.” Its status will be gray, meaning “inactive.” It will not be shown in green unless you activate the pool (which deactivates the parent pool).
Backups of the parent pool’s desktops will be copied to the recovery region starting at the scheduled backup time.
Before the backup, the desktop list will say, “No data available.” After the backup, the recovery region’s list of desktops will no longer be empty.
The desktops in the recovery region may show a Status of “Error.” This is normal.
Enabling Regional DR
To enable Regional DR on a pool, go to the Action menu of the recovery pool (not the parent pool) at “Resources > VDI Pools > Manage Regional DR Virtual Desktop Pools > poolname > Action” and select “Activate Regional DR.”
You will be asked to confirm activation. Read the warning popup first.
The following will happen:
The parent pool shuts down, ending any Client desktop sessions. (In the case of an actual regional failure, the desktops have already failed, so this makes no difference. If the pool is live, it interrupts the users.). The parent pool is marked as locked, with a red padlock icon.
A notification email is sent.
The status of the recovery pool is updated as shown:
Workspot Control informs the Workspot Clients that the parent pool is unavailable and the recovery pool is available. In the Client main window, the icon for the parent pool disappears and that of the recovery pool appears. If the two pools have similar names, users might not notice the switch.
It takes time for the recovery pool to activate. Currently, the state of the individual desktops may be briefly incorrect (perhaps showing an “Error” state when there is no error). This is self-correcting.
Users who attempt to connect in the interval will see error messages, including a “no desktops available in the pool” messages.
Control users will not see an accurate picture of the state of the recovery desktops until the pool is back up. Desktops that are booting may show error states instead.
Give the process half an hour to show signs of success before assuming that anything might have failed.
Once active, the recovery pool gives its users their recovery desktops and everything works as before.
Since the desktops are from a periodic backup, they will be slightly out of date. In most cases, this difference will be hard to detect.
The other infrastructure that users depend on (file servers, network servers, etc.) must also be accessible to the Regional DR subnet. None of this can reside solely in the parent region or a regional outage will render the recovery pool unusable.
Using Regional DR
During Regional DR, desktops operate as usual, and the usual administrative options in Workspot Control (reboot VM, redeploy VM, log off, etc.) are available.
Backups are not performed on the Regional DR pool.
Few pool options can be changed during Regional DR. In particular, you can’t add new desktops to the pool during Regional DR. Most fields in the “Edit Pool” page are grayed out, as shown below.
Deactivating Regional DR
To disable Regional DR, go to the Regional DR pool’s Action menu and select “Deactivate Regional DR.” This follows essentially the same process as activating Regional DR in reverse. The Regional DR pool is shut down, the parent pool is activated, and the Workspot Client connects users to the parent pool instead of the Regional DR pool.
Schedule. The transition from the Regional DR pool to the parent pool can either take place immediately (“Schedule now”), at a scheduled time (“Schedule at”), or as each user signs out of their Regional DR desktop (“On Log Off”). If “On Log Off” is selected, the date/time fields specify when to stop waiting for users to log off and to force the transfer. The transfer process logs off any remaining users.
Reactivation Action. Workspot Control can either transfer the desktops from the Regional DR pool back to the parent pool or reactivate the original desktops from the parent pool.
Once the Regional DR deactivation process is complete, the users have access to their desktops in their parent regions. Their Workspot Clients will be informed of this by Workspot Control automatically.
Workspot recommends deactivating Regional DR during a maintenance period when few desktops are active, since users will have no access to their desktops until the parent pool is back in operation.
Re-Enabling Backups to the Recovery Region
After disabling Regional DR, your recovery region desktops are left in place. You must delete them in Control to signal that you are done with them and backups to the recovery region can restart.
Note: Regional DR backups will not resume until you delete the desktops left over in the recovery region from the previous Regional DR event.