Dynamic cluster versioning for a group

An apparatus, program product, and method update the cluster infrastructure version used by a group resident in a clustered computer system without requiring a shut down of the group during the update. The cluster infrastructure software in individual nodes in the clustered computer system is updated while the group is maintained in an active state. After the cluster infrastructure software is updated, the group is then notified of the update. In response to the notification, the cluster infrastructure version used by the group is dynamically updated to that of the updated cluster infrastructure software, thus making additional functions supported by the new version of the cluster infrastructure software available for use by all group members.