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What does (Synchronized) after the database name mean in SSMS.

I just found a database at our client side, which contains (Synchronized) after the database name. enter image description here

I wanted to know, why this is happened?

Solution

  • High availability is a concept in sql which helps masks the effects of a hardware or software failure and maintains the availability of applications so that the perceived downtime for users is minimized.

    There are multiple ways by which this can be achieved. One of the ways is using adding multiple servers containing the same database to the availability group using 'AlwaysOn high availibility' feature which is found in object explorer below the databases.

    enter image description here

    In this feature, only one machine\server is called primary and others in the group are considered secondary nodes. Primary node always has read-write permissions and secondary nodes will only be in read modes there by we can ensure data quality even. Secondary nodes always will be in synchronized mode as they continuoulsy sync data from primary nodes and if you have access to primary node, the DB there will be in synchronizing mode.

    The machines in the availability group can be found as below

    enter image description here

    You can get more info here:

    Always On availability groups: a high-availability and disaster-recovery solution

    The Always On availability groups feature is a high-availability and disaster-recovery solution that provides an enterprise-level alternative to database mirroring. Introduced in SQL Server 2012 (11.x), Always On availability groups maximizes the availability of a set of user databases for an enterprise. An availability group supports a failover environment for a discrete set of user databases, known as availability databases, that fail over together. An availability group supports a set of read-write primary databases and one to eight sets of corresponding secondary databases. Optionally, secondary databases can be made available for read-only access and/or some backup operations.

    An availability group fails over at the level of an availability replica. Failovers are not caused by database issues such as a database becoming suspect due to a loss of a data file, deletion of a database, or corruption of a transaction log.