Upgrading Older Servers
When you upgrade an older server to Mountain Lion Server, you first install the Mountain Lion client on top of the old OS, and then you download and install the server components, as described in the preceding section. Upgrading requires Mac OS X Server 10.6.8 or later.
Upgrading from Lion Server (10.7) is a smoother process and retains more data than upgrading from Snow Leopard Server. The next few sections describe what you can expect.
What’s not moved from Snow Leopard Server
Mountain Lion Server doesn’t include several services and features that were part of Mac OS X Server 10.6. When you migrate or upgrade from version 10.6, the settings and data for these items will not be moved to Mountain Lion Server:
Windows Primary Domain Controller (PDC) or Backup Domain Controller (BDC)
Wiki-based mailing list and archives
Apache Tomcat and Apache Axis web services
QuickTime Streaming Server (QTSS)
NetBoot images that were ...