Pacemaker 2.0 is a major release whose main goal is to remove support for deprecated legacy syntax, in order to improve code maintainability.

Rolling upgrades from Pacemaker versions earlier than 1.1.11 are not possible, even if the underlying cluster stack is Corosync 2 or greater (the only stack supported by both Pacemaker 1 and Pacemaker 2). Rolling upgrades from Pacemaker versions 1.1.11 and later on top of Corosync 2 or greater should be possible with little to no change.

The changes fall into these categories:

• Pacemaker 2.0 Configuration Changes
• Pacemaker 2.0 Daemon Changes
• Pacemaker 2.0 Tool Changes
• Pacemaker 2.0 API Changes

Also, portions of the Pacemaker Explained document were separated into a new document, Pacemaker Administration. Pacemaker Explained now focuses solely on configuration options, while cluster administration tips are in the new document.