Database Mirroring

Asynchronous Database Mirroring vs. Asynchronous Availability Groups

Last Updated February 9, 2017

Always On Availability Groups, Database Mirroring, SQL Server

When Database Mirroring came out in SQL Server 2005 Service Pack 1, we quickly dropped Log Shipping as our Disaster Recovery solution. Log Shipping is a good feature, but I can failover with Asynchronous Database Mirroring faster than I can with Log Shipping. When Always On Availability Groups (AG) came out in SQL Server 2012,…

A funny thing happened on my way to set up Mirroring…

Last Updated February 9, 2017

Erik Darling

Database Mirroring, SQL Server

I’ve set up Mirroring about a billion times I’m not bragging about that. I’d rather say that I set up a billion AGs, and not one of them ever failed. But then I’d be lying to you; those things fail like government programs. One thing I’d never done, though, is set up Mirroring with a…

Failing over an Asynchronous Mirror in SQL Server (video)

Last Updated February 9, 2017

Kendra Little

Database Mirroring

Will a long running open transaction block you from changing to synchronous mode and failing over to your SQL Server database mirror? Join Kendra to test performing a planned failover from an asynchronous database mirror. Brent Says: Often, when I’m working with developers, they’re totally surprised that SQL Server’s failover methods all break in-flight transactions. No matter…

What Amazon RDS for SQL Server Users Need to Know about Multi-AZ Mirroring

Last Updated February 10, 2017

Brent Ozar

Amazon Web Services (AWS), Database Mirroring

Amazon Relational Database Service (RDS) now supports multi-availability-zone SQL Servers. This means you can have a primary database in one data center, and a secondary replica in another data center. Those Portland folks were always a little bit backwards anyway. When your primary server goes down, OR when the entire AZ goes down, you can fail…

Mirrors aren’t backups

Last Updated February 9, 2017

Brent Ozar

Architecture, Backup and Recovery, Database Mirroring

Are you using any of these technologies as a method of database protection? Database mirroring (keeping two database servers synchronized with the same data via SQL 2005/2008) Replication (copying records between databases) Log shipping (copying log files to another server and restoring them immediately) SAN-based mirroring (storing two copies of your database on two different…