Categories
High Availability

Types and Operating Modes in Mirroring

Mirroring offers two methods for exchanging data, lets discuss each one in detail.The two are

* Synchronous mirroring

* Asynchronous mirroring

Categories
High Availability

How can I bring mirror database online after principal server is down ?

Safety FULL with Witness :

Well the answer for this ‘depends on the mode in which mirroring is configured’. If mirroring is configured in High Availability mode (Full safety) then we don’t need to worry about failover as the mirror server will form a quorum with witness and will initiate an automatic failover. The safety level can be set using the below command,

Categories
High Availability

Introduction to Database Mirroring

Overview of Mirroring:

Mirroring is mainly implemented for increasing the database availability. Similar to log shipping mirroring is also implemented on per database basis. Database mirroring maintains two copies of a single database that must reside on different instances of SQL Server Database Engine (server instances). Typically, these server instances reside on computers in different locations. One server instance serves the database to clients (the principal server), while the other server instance acts as a hot or warm standby server (the mirror server).