Can you send the output of the script.

Just to add it will tell you the SPID that is causing the issue.
You might want to log SYS.SYSPROCESSES to a table too, if you don't have a monitoring...

select * from sys.dm_db_task_space_usage
where internal_objects_alloc_page_count <> 0

Get this to table, you can see what has been using TEMPdb and the amount of pages allocated and deallocated.

Why not script out the database objects and all, users tables , sprocs, triggers etc.
Then use the Import data wizard to copy the data across. Why do you need...

This has always worked for me.

http://blogs.msdn.com/b/mattm/archive/2012/03/23/ssis-catalog-backup-and-restore.aspx

USE SSISDB
BACKUP MASTER KEY TO FILE = 'c:\DMK\SSISDB\key'
ENCRYPTION BY PASSWORD = 'OLDKEY'

-----------------------------------------------------

As a starter

SELECT TE.name AS [EventName] ,
   T.DatabaseName ,
   t.DatabaseID ,
   t.NTDomainName ,
   t.ApplicationName ,
   t.LoginName ,
  ...

Not sure if I understand your setup but I have used FCI with AOAG. 2 FCI nodes for HA, 3 AOAG groops.

1 Primary( FCI for HA) x 2...

A full re-index rebuild will update stats. Is the DB being re-indexed every day?

select * from sys.dm_db_task_space_usage
where internal_objects_alloc_page_count <> 0

What has allocated pages in TEMPDB but not deallocated pages.

SELECT TE.name AS [EventName] ,
   T.DatabaseName ,
   t.DatabaseID ,
   t.NTDomainName ,
   t.ApplicationName ,
   t.LoginName ,
   t.SPID ,
   ...

Thanks for the replies. Most helpful. The server came back online and AOAG caught up.

I was going to ask how it did that when it was down for...

There are 3 nodes involved here, 

1 Priamry

2 Secondaries

Only one of the secondaries is out of sync.

Removing the Secondarires from the AG...

Perry Can that be done on a per replica basis.

All dbs are out of SYNC is this the best way to do it. Rather than remove the dbs from the AG and resync all replicas.

Yes about 10.