How to: Configure SQL Server 2012 AlwaysOn
Enabling the AlwaysOn Feature
Quick post on how to enable the AlwaysOn feature at the database instance level. This needs to be accomplished for each instance involved in the architecture. In our target architecture this will need to be accomplished once per node for the SQL Server Failover Cluster Instance (FCI) in data center 1 and once per node for the SQL Server FCI in data center 2.
MSDN has an exhaustive set of Prerequisites, Restrictions, and Recommendations. What I’ve done here are list some of the highlights which will apply to most setups.
- System Requirements
- Windows Server 2008 SP2, Windows Server 2008 R2 SP1, or Windows Server 2012.
- x86 or x64 only.
- Each computer must be a node in a Windows Failover Cluster (WFC)
- Each node must have a drive with the same letter as the other nodes.
- SQL Server Requirements.
- For Kerberos to work – all SQL instances need to run as the same domain account and SPNs must be manually registered.
- Enterprise Edition is required.
- All instances must use the same collation.
- Availability Group Listeners use only TCP/IP. All clients connecting must use TCP/IP.
Enabling AlwaysOn Feature
First step in our process is to enable the AlwaysOn feature for your instance. Repeat the following steps for each of your nodes and each instance which will be involved in AlwaysOn. This will require a service restart.
- Open the SQL Server Configuration Manager.
- Select SQL Server Services on your navigation panel on the left.
- Right click on the SQL Service and select Properties.
- Once the Properties window is open; select the AlwaysOn High Availability tab.
- Check Enable AlwaysOn Availability Groups.
- Click OK.
- Accept the warning message which pops up.
That’s it! Configuring the feature is the fastest and simplest part of this process. After reviewing my blog series plan, I probably should have merged this with my next part. Since I’ve already announced a 7 part series, though, I’ll just make sure to get part 4 out to you guys sooner than I had planned to make up for the lack of content here.
Follow the links below to move on through this tutorial.