You could configure a multi-node Always On Availability Group (AG), a feature of SQL Server itself, or you could use Windows Server Failover Clustering (WSFC) to configure a multi-node SQL Server ...

We'll be using Ubuntu 12.04 for our server, though Prosody is a cross-platform application and will run on Windows, OS X, and a number of different Linuxes. Strap in, grab your server, and let's roll!