The High Availability Extension now comes with the concept of a migration threshold and a failure timeout. You can define a number of failures for resources, after which they will migrate to a new node. By default, the node will no longer be allowed to run the failed resource until the administrator manually resets the resource’s failcount. However it is also possible to expire them by setting the resource’s failure-timeout option.

You can now set global defaults for resource options and operations.

Often it is desirable to preview the effects of a series of changes before updating the configuration atomically. You can now create a “shadow” copy of the configuration that can be edited with the command line interface, before committing it and thus changing the active cluster configuration atomically.

Rules, instance_attributes, meta_attributes and sets of operations can be defined once and referenced in multiple places.

The CIB now accepts XPath-based create, modify, delete operations. For more information, refer to the cibadmin help text.

For creating a set of collocated resources, previously you could either define a resource group (which could not always accurately express the design) or you could define each relationship as an individual constraint—causing a constraint explosion as the number of resources and combinations grew. Now you can also use an alternate form of collocation constraints by defining resource_sets.

Provided Pacemaker is installed on a machine, it is possible to connect to the cluster even if the machine itself is not a part of it.

By default, recurring actions are scheduled relative to when the resource started, but this is not always desirable. To specify a date/time that the operation should be relative to, set the operation’s interval-origin. The cluster uses this point to calculate the correct start-delay such that the operation will occur at origin + (interval * N).

All resource and cluster options now use dashes (-) instead of underscores (_). For example, the master_max meta option has been renamed to master-max.

The master_slave resource has been renamed to master. Master resources are a special type of clone that can operate in one of two modes.

The attributes container tag has been removed.

The pre-req operation field has been renamed requires.

All operations must have an interval. For start/stop actions the interval must be set to 0 (zero).

The attributes of collocation and ordering constraints were renamed for clarity.

The resource-failure-stickiness cluster option has been replaced by the migration-threshold cluster option. See also Migration Threshold and Failure Timeouts.

The arguments for command-line tools have been made consistent. See also Naming Conventions for Resource and Custer Options.

The cluster configuration is written in XML. Instead of a Document Type Definition (DTD), now a more powerful RELAX NG schema is used to define the pattern for the structure and content. libxml2 is used as parser.

id fields are now XML IDs which have the following limitations:

Some fields (such as those in constraints that refer to resources) are IDREFs. This means that they must reference existing resources or objects in order for the configuration to be valid. Removing an object which is referenced elsewhere will therefor fail.

It is no longer possible to set resource meta options as top-level attributes. Use meta attributes instead.

Resource and operation defaults are no longer read from crm_config.