Strange Login and AppDomain xx created

Question

On a sql 2k16, when I go through error logs, I find a lot of messages las follows

Server Date Process Count Text
SQL2K12 2021-03-15 13:30:44.640 spid17s 1 AppDomain 39 (MDS.mds_schema_user[runtime].38) unloaded.
SQL2K12 2021-03-15 13:00:15.550 spid62 1 AppDomain 40 (master.sys[runtime].39) created.
SQL2K12 2021-03-15 13:00:15.550 spid62 1 AppDomain 40 (master.sys[runtime].39) created.
SQL2K12 2021-03-15 10:00:43.090 spid45s 1 AppDomain 39 (MDS.mds_schema_user[runtime].38) created.

Not sure what this appDomain creating and unloading?
Thanks

Answer 1

That is completely normal and expected when you are running MDS.

Answer 2

Hi again all, I removed the MDS (uninstall), 2 things:

• NDS Db is still there sitting in SQL and I switched to off status
• Still getting the messages in the error log
  SQL2K12 2021-03-15 13:30:44.640 spid17s 1 AppDomain 39 (MDS.mds_schema_user[runtime].38) unloaded.
  SQL2K12 2021-03-15 13:00:15.550 spid62 1 AppDomain 40 (master.sys[runtime].39) created.
  SQL2K12 2021-03-15 13:00:15.550 spid62 1 AppDomain 40 (master.sys[runtime].39) created.
  SQL2K12 2021-03-15 10:00:43.090 spid45s 1 AppDomain 39 (MDS.mds_schema_user[runtime].38) created.

Answer 3

OK, but in any case, I went trhough all jobs (8 or 9) on the named instance, 4 of them are installed by sql whic were has added during setup, the rest are 5 jobs created by maintenance script from https://ola.hallengren.com, so really where does this
salam\sql2k12$ on ip ::1.
I just double checked my users in the domain, no such user, double-checked login in sql server, it cant find any such thing

Answer 4

I have 5 or 6 jobs in the named instance, while I was checking, I noticed that the SQL Agent in the named instance runs under a user

NT SERVICE\SQLAgent$SC2K12

After reading the thread
https://social.msdn.microsoft.com/Forums/sqlserver/en-US/9e6bb2de-8fd0-45de-ab02-d59bbe05f72e/servicedatabase-accounts-nt-servicemssqlserver-amp-nt-servicesqlserveragent-8230-what-are#:~:text=The%20SQL%20Server%20Agent%20runs%20as%20a%20Windows,what%20it%20should%20do%3B%20and%20then%20do%20it.
I understood that I should have a group where those users are listed which is not the case when I run

lusrmgr.msc

Answer 5

I monitor both error logs for default and named instance with the same powershell script and it populates a table, 1st column in this table is SQLInstance anme

The email/alert I receive from my script that runs every 1 hour indicates an error in the default instance as noted above, again here it is