We have TFS Version 15.105.27412.0 installed on a server (Server A) and have it configured to point at our database server (Server B).
We have the two TFS databases (
ServerB and they are mirrored with
ServerC, however the connection string in the configuration manager for TFS is not "mirroring aware" - see screenshot below from TFS Administration Console
Furthermore, if I interrogate the TFS configuration database as follows
SELECT * FROM Tfs_configuration.dbo.tbl_Database
This confirms the connection strings for both databases do not have failover partners specified.
We had a planned failover this morning from
ServerC which included both of the
TFS databases and much to everyone's surprise,
TFS continued to function with the databases
failover and running on
I stopped the SQL Server service on
ServerB and ran an
ExtendedEvents session on
ServerC (looking for queries that accessed the
TFS databases) and can confirm that the
TFS application was indeed querying
How did this happen? The TFS installation has no idea that
ServerC exists, is something happening at the SQL Server level?