I noticed the following message in the SQL Server ErrorLog for one of the database servers which is in a database mirroring setup (currently the mirror).
Error: 1438, Severity: 16, State: 2
The server instance Witness rejected configure request; read its error log file for more information. The reason 1427, and state 31, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry.
I ran the following TSQL on the mirror database server:
SELECT DB_NAME(database_id) AS 'DatabaseName' , mirroring_role_desc AS 'DatabaseRole' , mirroring_role_sequence AS 'FailoverCount' , mirroring_partner_instance AS 'MirroringInstance' , mirroring_state_desc AS 'MirroringState' , mirroring_connection_timeout 'MirroringConnectionTimeoutInSeconds' , mirroring_witness_name AS 'WitnessInstance' , mirroring_witness_state_desc AS 'WitnessState' FROM master.sys.database_mirroring WHERE mirroring_guid IS NOT NULL
and noticed that one of the database’s WitnessState value was Disconnected. To resolve the issue I ran the following TSQL on the principal database server and the message stopped appearing in the Error Log.
ALTER DATABASE [DatabaseName] SET WITNESS OFF GO ALTER DATABASE [DatabaseName] SET WITNESS = 'TCP://ServerName.Domain.Com:5022' GO