The AlwaysOn 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, AlwaysOn 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.
In the process of configuring AlwaysOn Availability Groups, the first step is to configure Failover Clustering on the participating servers.
To configure the Failover Cluster
Open "Server Manager" and choose "Add Roles and Features"
Select "Failover Clustering" and Add Dependency Features
Add Features and Click Next
Once you click next, the wizard will start the installation
With this, the required failover clustering components are installed.
Now we need to create the cluster and before that we need to validate the participating servers for creating cluster.
Open "Failover Cluster Manager" and choose "Validate Configuration"
Add the Servers
Choose to Run All Tests and Click Next
Click Next in the confirmation page
You can ignore the disk related warning in the case of AlwaysOn
Click Finish and Create the new Cluster
Assign a Name and IP to the cluster
Uncheck "Add all eligible Storage to the Cluster" and click next
On the successful completion of this wizard, the process of configuring the cluster will be completed.
Now we are all set to configure AlwaysOn Availability Groups.
In the next post, we will learn how to Enable and Configure the AlwaysOn Availability Groups using SQL Server 2016.