AlwaysOn Availability Groups
Figure 45.1 also shows the availability group capability. Availability groups are focused on database-level failover and availability by utilizing a data redundancy approach. Again, borrowing from the database mirroring experience (and underlying technologies), a transactionally consistent secondary replica is made that can be used for both read-only access (active for use at all times) and for failover if the primary database (primary replica) fails for any reason. In Figure 45.1, you can see a SQL Server AlwaysOn Availability Group being used for HA and even for distributing the read-only workload off of the primary SQL Server instance to the secondary replica. You can have up to four secondary replicas in an availability ...
Get Microsoft SQL Server 2014 Unleashed now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
