Terry's Blog

Monitoring Your SQL Server 2005 Database Mirror Once you have a database mirror running, it is imperative to monitor the performance of the mirror, and in the case of high performance (asynchronous) mirrors, how far behind the mirror is compared to the principle. With high safety (synchronous) mirroring, performance is critical, as all transactions must be committed on the mirror before they can be committed on the principle. On a high performance mirror, a delay can mean the mirror isn’t as up to date as service levels require, and the transaction log can fill up as transactions cannot be backed up until they have been applied on the mirror. There are different tools for monitoring mirroring: Database Mirroring Monitor (SQL Server Management Studio) Perfmon Counters Catalog Views Database Mirroring Monitor To launch the Database Mirroring Monitor, right click on the database in SSMS, select "Tasks", then "Launch Database Mirroring Monitor&qu