Feature Request: Only backup logs from primary in AG

[somethingsomething]

We have a backup job with multiple VMs that have multiple SQL AGs that span across them.

The desired behavior is that VEEAM will backup transaction logs from each AG from whichever server is the PRIMARY. We have the SQL Backup preferences set to "Primary" for automated backups but I've learned that the VBR selection logic is more complicated than that and in many cases will result in the SECONDARY being used.

The reason for wanting the primary is that it's more reliable. As long as the primary remains the primary, it'll never end up in a RESOLVING state resulting in the inability to pull backups. Our DBAs also have requested this as well. With multiple VMs and multiple overlapping AGs, being able to select there the logs are pulled from is strongly desirable.

CaseID is 02429498

[veremin]

What happens if you tweak SQL backup preferences settings? Thanks.

[somethingsomething]

What happens if you tweak SQL backup preferences settings? Thanks.

Thanks for the suggestion.

The short answer is that they're essentially ignored. The backup preference is only a very small portion of the algorithm that VEEAM uses when selecting which node to backup transaction log from. In most cases, whichever node finishes the nightly (image) backup first will end up being the primary.

The reason I opened this was because VEEAM Support confirmed there wasn't a way to force it to use the primary. If you look at the Case#, you should see that QA was consulted in the behavior.

[veremin]

Got it, feature request noted. Thanks.

[somethingsomething]

Got it, feature request noted. Thanks.

Thank you sir! Appreciate it.

[johannesk]

I've had to deal with some strange transaction log behavior of SQL availability groups.

getting messages like:

Skipping databases to be backed up from another SQL Server node

This explained why it is as it is. Note the 5 points in the end of the article.

https://helpcenter.veeam.com/backup/vsp ... pport.html

I actually have not had problem with this since the 9.5 U2 version. But I did a RFE here at the time we had problems with this.
veeam-backup-replication-f2/rfe-sql-log ... 34951.html

[somethingsomething]

Yep, I'm familiar with that article. It does a good job explaining the criteria of what makes a node eligible, but unfortunately Backup Preference in SQL is largely unimportant.

The fact that you have to have all VMs in an AG in the same backup job is also a frustrating limitation when you're backing up transaction logs (Especially with large VMs). Otherwise, you have jobs that are fighting eachother over the transaction logs.