Platform: Mac OS X Server
Introduction and announcement; not a sales date.
Apple source ↗On June 6, 2011, Apple announced July availability for Lion Server at US $49.99, requiring Lion. The US July 20 release confirmed Mac App Store availability. Server was not a standalone $49.99 complete operating system without Lion: the client was separately priced at $29.99. These are historical US prices, not a current offer or a total charged to every buyer.

Apple · Lion / Server · 2011-06-06 · Apple · Lion / Server · 2011-07-20 · US
Apple's technical specifications list Profile Manager for client management, alongside iCal Server 3, Wiki Server 3, iChat Server 3 and Address Book Server 2. Mail combined Postfix, Dovecot and RoundCube; web services included Apache and PostgreSQL. NetBoot, NetInstall, NetRestore and Software Update Server remained in the package. This describes that product, not services Apple necessarily maintains today.
Apple · Lion Server · Technical Specifications
For upgrading, Apple specified Intel Core 2 Duo, Core i3, i5, i7 or Xeon, 2 GB memory and 10 GB free, starting from OS X 10.6.6 or later with 10.6.8 recommended. An upgrade path from Snow Leopard does not remove Server's Lion requirement. The administration list distinguishes Server app, Server Admin and Workgroup Manager; it was not one tool doing everything.
Apple · Lion / Server · 2011-07-20 · US · Apple · Lion Server · Technical Specifications
In Macworld, John C. Welch criticized switching between tools and thin documentation, while praising Profile Manager and iOS device management. His review states that he tested 10.7.1 and reports OpenLDAP and Active Directory difficulties. Those observations are not applied unqualified to launch-day 10.7, every installation or later versions; his hope for improvement does not establish that a fix arrived.
John C. Welch · Macworld · 2011-11-01 · 10.7.1
Selected releases, not a complete history. Dates follow Apple's release records, not the latest page edit. No builds are included.
ISO date: year-month-day.
Platform: Mac OS X Server
Introduction and announcement; not a sales date.
Apple source ↗Platform: Mac OS X Server
Mac App Store availability per the US announcement; requires Lion.
Apple source ↗