Seaquel
SQL Server error code

SQL Server error 1479

SQL Server raises error 1479 at severity 16, which marks a problem with the query or data that you can correct.

The mirroring connection to "%.*ls" has timed out for database "%.*ls" after %d seconds without a response. Check the service and network connections.
Msg1479
Severity16
Group1000–1999

Source: Database Engine events and errors