Before you do that. What is your goal ?

I would suspect the AD SPN.

I recall our cluster losing full control over that object during our tests.

Broke it down and rebuilt it. Never happened again. We built 10+ 2node...

Did you enable the AlwaysOn XEvents session on all involved instances?

Did you install a monitoring solution to get an overview of failover events,..

I have a sqlagent job that is launched...

did you check with all prerequisites ?

Prerequisites, Restrictions, and Recommendations for Always On availability groups

• This reply was modified 1 week, 6 days ago by  Johan Bijnens.

BTW What's the advantage of an AG if you really need it to be hosted on a given server ?

It should be consumable in either situation.

Check the SQLServer errorlog file !

Try the failover to A manually in SSMS and see what error comes up.

Implement failover monitoring so you can see which fases it passes or...

What's wrong with a simple ALTER INDEX cl_ix ON schema.table REBUILD ... ? ( as that does not impact the non-clustered indexes )

Keep in mind this will also interfere with...

• This reply was modified 5 months ago by  Johan Bijnens.

replay the deadlock with SentryOne PlanExplorer (free) ! It shows what is happening and causing the deadlock !!!

btw: this is the...

I would suggest BOL : https://docs.microsoft.com/en-us/sql/database-engine/availability-groups/windows/failover-and-failover-modes-always-on-availability-groups

Try to break it in your DBADEV environments, then figure out what and how to fix it. #YourMindIsYourStrength

Shrink file is the better choice because of its scope
Keep in mind you need to rebuild all indexes in that file after your shrink datafile ( not log )...

With SQLServer 2017 or the current Azure SQL Managed Instance, you also need to set configuration clr strict security to 0 !
( it is 1 by default !!...

did you perform full database maintenance after the upgrade to the new engine ?

You've seen the "missing index", right ?

What's the cluster service account ? Does it have AD auth to register computer objects ?

You have to register the Listener computer object in AD yourself and grant the cluster computer object full authority to manage that listener object !

I always configure it using Powershell.
As marked: did you restart the cluster resource to enable the listener ?

# create listener with default DHCP
$NewAGListener =...