The principal and mirror servers communicate and cooperate as partners in a database mirroring session. When the session is not synchronized, the mirror server is typically available as a warm standby server, but there is a risk of minor data loss. When a database mirroring session is synchronized, database mirroring provides a hot standby server that supports rapid failover without a loss of data from committed transactions. The other instance acts as a hot or warm standby server, or more specifically the mirror server, depending on the configuration and state of the mirroring session. One server instance serves the database to the client, or the principal server.
When you implement database mirroring on a database, it initiates a relationship, known as a database mirroring session, between these server instances. Typically, these server instances are physically located at different sites. These two copies reside on different server instances of the SQL Server Database Engine. SQL Server Database Mirroring, a Brief Overviewĭatabase mirroring works by keeping two copies of a single database. In this tutorial, we will also be showing you how you can verify your configuration in a final appendix.
In this tutorial, we will take advantage of the database mirroring feature of Microsoft SQL Server and tell you how to backup and restore your content.Īs a bit of a heads up, in this tutorial, we will carry out the following steps: During a migration from an Microsoft SQL Server database to Alibaba Cloud, you have the choice of either migrating to an Alibaba Cloud Elastic Compute Service (ECS) hosted database or migrating directly to an Alibaba Cloud ApsaraDB for RDS database instance.