I've added a DB to an availability group.
There are a few dbs in there, and all of them both seeded and syncing fine to the secondary.
This last one gets added to the AG ok it would seem, but is marked as "not synchronizing".
I've taken it out and put back in, same thing.
I've looked in extended events, event viewer... nothing. Clicking on "warnings" in the dashboard says nothing useful. DB files do not exist on the secondary at all. Suspect it must be blocked right at the start of its seeding process (but clearly after the initial validations in the "add to AG" wizard).
I have this distinct feeling SQL server must be logging something to some DMV I'm not aware of, with the reason.
Is there a canonical guide to ALL the places one is supposed to look for AlwaysOn related errors?