Problem

SQL Server 2005 database mirroring is not working. Automatic failover does not happen when the principal or mirror servers are down. You will receive the following error messages in the event logs.

	Event Type:	Error
	Event Source:	MSSQLSERVER
	Event Category:	(2)
	Event ID:	1479
	Date:		4/24/2008
	Time:		12:00:43 AM
	User:		N/A
	Description:
	The mirroring connection to "TCP://xxxx.yourdomain.com:5022" has timed out 
	for database "yourdatabase" after 10 seconds without a response.  
	Check the service and network connections.
	

Solution

The default mirroring time out value is 10 seconds. You need to increase this number if you have more and more database transactions.

1. Open your principal database with SQL Server Management Studio.
2. Open a new SQL query windows and execute the following statement

		ALTER DATABASE yourdatabase SET PARTNER TIMEOUT 30