Inactive mailbox - how to backup these using VBM365

[sumeet]

Hello,

Our client for whom we are backing up their M365 using VBM365. This is all good for active mailboxes.
But they also have thousands of inactive mailboxes. They want these to be backed up by VBM365, so that they can remove the retention from these inactive mailboxes and can delete them.

For Veeam to backup these mailboxes, they will first need to be either recovered (https://learn.microsoft.com/en-us/purvi ... ve-mailbox) or restored (https://learn.microsoft.com/en-us/purvi ... ve-mailbox).

• Has anyone done such an exercise?

• Which is the best option - recover an inactive mailbox or restore an inactive mailbox

• In case of restore an inactive mailbox, a different name mailbox will have to be created that will be target of restore

• But for recover inactive mailbox, the same name mailbox will be recovered - which will be more helpful when a restore request comes

Any other suggestions or pointers that can help?

We do understand that additional licenses will be required for both M365 and Veeam, this is fine.

Thanks,
-Sumeet.

[Mildur]

Hi Sumeet

I would use just recover the account.
Attaching the mailbox to another user account doesn't make much sense to me.

We do understand that additional licenses will be required for both M365 and Veeam, this is fine.

A workaround for the licensing could be changing the type from UserMailbox to SharedMailbox. Veeam doesn't ask for licenses when protecting Shared Mailboxes.
The change has to be done on Exchange Online after you have recovered the mailbox. But you should check with Microsoft first if they allow to change thousands of UserMailboxes to the type Shared.

Best,
Fabian

[Polina]

+1 to converting to shared mailboxes; this seems to be the easiest way

[sumeet]

Hi Fabian and Polina,

Thanks for the inputs. I will discuss with my client.

Have a good weekend.

-Sumeet.

[sumeet]

We tried few recovery options and cannot get it to work.

With the error, I found the Microsoft article that we cannot use the recover option when the domain is federated.

https://answers.microsoft.com/en-us/out ... cc7c716173

Any inputs?

[Mildur]

Hi Sumeet

In that case (local active directory not available anymore) you must restore the mailbox to a new Entra ID user account.
Veeam Backup for Microsoft 365 requires an active mailbox. And an active mailbox requires an active Entra ID account.

Best,
Fabian

[sumeet]

Hi Fabian,

Thanks for the confirmation.

This will be a mammoth exercise for us to backup 2500+ inactive mailbox.
Any process that can simply this for us?

For now, this is our high level plan,

1. Create a M365 group and exclude this M365 group from the current mailbox backup job (which runs daily for the active mailboxes)
2. Create new Entra ID user account (not sure yet on the naming convention for this new user account)
3. Add this new Entra ID user account to the M365 group
4. Restore the mailbox to this new ID user account
5. Once the restore is complete, setup a separate mailbox backup job specific to just this M365 group
6. Wait for this job to complete
7. Delete the Entra ID account
8. Delete the inactive mailbox

The reason for creating the M365 group and excluding it from the primary mailbox backup job is to make sure this job continues to run daily and is not slowed down by the restores of inactive mailboxes.
Once we have validated these steps and are successful, for steps #2, #3 and #4, we will increase the count to 200+ mailboxes at a time to be restored and backed-up.

Are we missing anything or any better way to get this done?

[sumeet]

Hi Fabian,

We have completed this exercise by using the above process for 3000+ mailboxes.

We have to do similar for OneDrive of inactive users. Will start a separate thread. Please help if you have inputs.