Configure cluster on an existing SQL Server - to setup AlwaysOn Availability Groups

Question

We are already having an SQL Server Enterprise Edition instance running on an Physical Server. Now to configure AlwaysOn Availability Groups

1. Can we configure WSFC (Windows Server Failover Cluster) Services on existing SQL server instance?
2. Or uninstall SQL Server, install WSFC and then install SQL again? (this may not be a best thing, as they are holding huge DB's.)

As we are planning a 3-node (all are physical machines and currently running SQL instances) cluster, how to move ahead? What options to select from the installation media to proceed with AlwaysOn Availability Groups configuration. Thanks

• Ben Thul: I'm fairly sure that you can enroll an existing server into WSFC without needing downtime. If it's not already part of a cluster, you may need a downtime to add AG capability to the server - I don't remember if it takes the instance offline to do that or not.

Answer 1

You can do it without sql reinstall. Only some reboots.

Install WSFC, add nodes with existing sql server.

Then enable alwayson in the configuration manager:

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