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SQL Server Database mirroring modes and patner timeout

The Two modes of Database Mirroring in SQL Server for HA/DR Solutions are

  1. Synchronous mirroring( High Availability / HA )
  2. Asynchronous mirroring( Disaster Recovery / DR )

Synchronous mirroring :

In all SQL Server databases, data changes are recorded in the transaction log before any changes to actual data pages are made. The transaction log records are placed first in a database’s log buffer in memory, and then flushed to disk (or ‘hardened’) as quickly as possible. In database mirroring, as the principal server writes the principal database’s log buffer to disk, it simultaneously sends that block of log records to the mirror instance.The mirror receives the log records in mirror database’s log buffer and then hardens them to disk … Read the rest