Does anyone know how to change the data location of Mac OS X Server (v3) Software Update?
I'd like to move it to a large RAID permanently connected to the server but I can't find the command in serveradmin.
The easy and official way is to relocate all services' data via Server.App -> Your Server -> Settings -> Service data location (or similar).
If you just want to change the data store of Software Update Server, you could try altering the string of "updatesDocRoot" in /Library/Server/Software Update/Config/swupd.plist. Don't forget to restart Software Update Service after your operation.
Hope that helps.