I'm trying to install the new SP2 for SQL Server 2016, but it fails during the install with an Engine error. This is what I can read in the errorlog>
Error: 468, Severity: 16, State: 9.
Cannot resolve the collation conflict between "Latin1_General_CI_AS" and "SQL_Latin1_General_CP1_CI_AS" in the equal to operation.
The failed batch of t-sql statements :
CREATE PROCEDURE sp_sqlagent_get_perf_counters @all_counters BIT = 0 AS BEGIN ...
Error: 912, Severity: 21, State: 2.
Script level upgrade for database 'master' failed because upgrade step 'msdb110_upgrade.sql' encountered error 200, state 7, severity 25. This is a serious error condition which might interfere with regular operation and the database will be taken offline. If the error happened during upgrade of the 'master' database, it will prevent the entire SQL Server instance from starting. Examine the previous errorlog entries for errors, take the appropriate corrective actions and re-start the database so that the script upgrade steps run to completion.
Error: 3417, Severity: 21, State: 3.
Cannot recover the master database. SQL Server is unable to run. Restore master from a full backup, repair it, or rebuild it. For more information about how to rebuild the master database, see SQL Server Books Online.
SQL Server shutdown has been initiated
The master database was running "Latin1_General_CI_AS" and MSDB (and other dbs) was running "SQL_Latin1_General_CP1_CI_AS".
I have new backups of all databases on the server including master and msdb.
I'm tempted to try to restore the master master as shown in https://docs.microsoft.com/en-us/sql/relational-databases/backup-restore/restore-the-master-database-transact-sql?view=sql-server-2017
But I'm trying ensure that it will actually work, and not just make the situation worse.
How do I get my SQL Server back up and running?
EDIT: I've started the mssqlserver service like this:
NET START MSSQLSERVER /T902
This gets the server started, and I've looked into msdb110_upgrade.sql, and found quite a few missing "COLLATE DATABASE_DEFAULT"s which I've added.
But it is not taking my changes.