Failover Cluster Archives

Microsoft SQL Server

SQL Server recovery time

Post author:Tomas Lind
Post published:2015/10/27
Post category:Error log Failover Cluster System Stored Procedures
Post comments:0 Comments

SQL Server Recovery time is the time it takes for SQL Server to rollback or roll-forward transaction not yet persisted to the database after a service restart. Transactions that are uncommitted are rolled back, and transactions that are committed but not yet persisted are rolled forward.

Depending on the volume of transactions that needs to be handled during recovery, recovery may take a long time to perform. This affects the time it takes for a SQL Server restart. Another example when recovery times become a factor is when a failover is done in a SQL Server cluster.

So how can we know how long the recovery time will be?

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Microsoft SQL Server

Manual failover in a SQL Server cluster

Post author:Tomas Lind
Post published:2014/04/15
Post category:Failover Cluster
Post comments:7 Comments

In this blog post, I’ll demonstrate how to find the currently active node in a SQL Server cluster, and how to do a manual failover to another node.

Note that a failover will result in a short down time for your SQL Server environment. This is because a recovery (rollback and roll forward of transactions) will be performed on the new active node in the SQL Server cluster. In an environment with long running transactions, the time for the recovery may be substantial (how to check the latest recovery time). So don’t do failover in a production environment unless absolutely necessary. Preferably, use a cluster lab environment to test things out first.

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