Best way to preserve Exchange on-prem mailboxes for deleted user accounts?

[StoopidMonkey]

In VBO for 365 they make this process dead simple. If a mailbox is deleted it is still retained in the backup database for [x] years depending on how it was configured. In VBR for on-prem Exchange backups it's less clear. If we have a disabled user account that we delete it then deletes the mailbox from Exchange. As best as I can tell once the mailbox is gone it is also not visible in Exchange Explorer for the latest restore point. Does this mean I should rely on GFS copies to find a mailbox that was deleted a year ago? Should I be tweaking the on-prem Exchange retention settings such that these mailboxes are still visible in Veeam backups? Or should I just be exporting these mailboxes to PSTs before deleting the accounts?

[PetrM]

Hi Chris,

Was the mailbox removed before the latest restore point was created?

Thanks!

[StoopidMonkey]

This isn't a live controversy, just thinking of how best to deal with stale mailboxes from long-disabled user accounts. We'd like to delete those user accounts to clean things up a bit. What my testing seems to indicate so far is that if Deleted Mailbox Retention is configured right at the Database level then the mailbox should be visible in the Veeam Explorer browser for all recovery points within the Deleted Mailbox Retention window. I may just migrate all the old mailboxes to a separate database and set the DMR to 10 years if this pans out. I won't recover any disk space but it will clean up the user account lists for sure.

[PetrM]

Hi Chris,

At first glance, the idea sounds absolutely reasonable. However, I need some time to think more deeply about potential pitfalls and maybe carry out a couple of tests.

Thanks!

[PetrM]

Hi Chris,

Looks like there are no special recommendations related to VEX to cover this specific use case. Regarding the Exchange database, I don't think I can propose anything better than what you already have in mind, simply because nobody knows your infrastructure better than you do.

Basically, you can move the deleted mailboxes to a dedicated database with a 10-year DMR and keep these mailboxes in both the database and a backup (just make sure the database is backed up). Alternatively, you can set a 10-year backup retention policy and open a backup in VEX or export it to a .pst file to open in Outlook.

Thanks!