I’ve noticed that the Server.app installers for Mavericks and Mountain Lion have now vanished from my list of Purchases in the App Store, and searching for “OS X Server” will only give you the option of Server.app 4.0 for Yosemite. However, Server.app 2.2.5 for Mountain Lion and Server.app 3.2.2 for Mavericks are still available. You just need the right Mac App Store URL.
As of November 1, 2014, here are the Mac App Store URLs for Server.app 2.2.5 for OS X 10.8.5 and Server.app 3.2.2 for 10.9.5:
- Server.app 2.2.5: https://itunes.apple.com/us/app/os-x-server-2.2.5/id537441259?mt=12
- Server.app 3.2.2: https://itunes.apple.com/us/app/os-x-server-3.2.2/id714547929?mt=12
To help safeguard against a day where they may not be available at all, I recommend downloading a copy of the Server.app installer packages from the MAS.