About OS X Server 5.1
Learn about changes included in the OS X Server v5.1 Update.
This software updates OS X Server v5.0.3, v5.0.4, or v5.0.15. It requires OS X El Capitan v10.11.4 to install.
OS X Server v5.1 is the only version of Server that runs on OS X v10.11.4. If you upgrade a Mac running a previous version of OS X and OS X Server to OS X v10.11.4, you must upgrade to OS X Server v5.1 as well. If your Mac uses a version of OS X prior to v10.11.4, you must upgrade to OS X v10.11.4 in order to use OS X Server v5.1.
How to update
On Macs running OS X v10.11.4, update to OS X Server v5.1 from the Updates pane of the Mac App Store. To prevent the interruption of services, Server updates aren't automatically installed, even if you've chosen to install other updates automatically from the Mac App Store.
During installation you may see the message "Server app replacement detected." This is a normal part of the update process. All Server settings and data are preserved during the update.
After installation is complete, open Server app to finish setting up your previously configured services.
Included changes
OS X Server v5.1 improves the general stability of OS X Server and delivers the following specific improvements:
Updated for OS X El Capitan v10.11.4
Support for TLS 1.2
General Profile Manager performance improvements
Support for new Education features in iOS 9.3
Profile Manager
Support for Shared iPad
Support for iOS Classroom app
New payloads (supervised only): Notifications; Lock Screen Message
New Restrictions (supervised only): Allow Apple Music; Allow Radio; Allow Notifications Modification; Apps Shown on Home Screen
New Restrictions: Allow iCloud Photo Library
Support for installing major OS X updates
L2TP/IPsec VPN profiles now require 2048-bit or stronger Diffie-Hellman groups
Caching Server
Supports caching user data for Shared iPad
Performance optimizations for iCloud data caching