How do I dictate the order of preferred replica on a Always On cluster?

Question

I have a problem, I look after a massive estate. the newer AO clusters I built myself and they work fine. I have inherited once AO cluster which is often problematic. However, migrating isn't an option ATM.

My current problem is I notice Netbackup wouldn't take backups from the secondary. After investigation, I found it was trying to take the backup from the DR instance. I've set it to take from the Primary for now.

Current behaviour

AUTOMATED_BACKUP_PREFERENCE = PRIMARY

preferred replica results

DR = 0

primary = 1

secondary = 0

AUTOMATED_BACKUP_PREFERENCE = SECONDARY_ONLY

preferred replica results

DR = 1

primary = 0

secondary = 0

The behaviour I need it to be is how can I get it to be,

AUTOMATED_BACKUP_PREFERENCE = SECONDARY_ONLY

preferred replica results

DR = 0

primary = 0

secondary = 1

However I can't find anything on Microsoft to point me in the right direct?

Answer 1

You can set the backup Priority to be higher on your non-DR node

By curiosity, why are you taking backup on the secondaries ?

There is some cases where your secondary could be out of sync with the primary (even if you set you AG to by Sync), for that reason, I usually prefer to have my backup done on my primary node.

Also, if you take the backup on the secondary node, are you also running checkdb on that secondary node ? (you don't want to end up doing backup of a corrupted secondary)