You have a JBOSS cluster.
Identity Manager appears to be up but many tasks appear to be failing. The application server log for one or more of the nodes contains the error:
017-04-26 08:02:27,538 ERROR [org.jboss.kernel.plugins.dependency.AbstractKernelController] (main) Error installing to Start: name=jboss.messaging:service=PostOffice state=Create mode=Manual requiredState=Installed java.lang.IllegalArgumentException: Cannot start post office since there is already a post office in the cluster with the same node id (0). Are you sure you have given each node a unique node id during installation?
The above error indicates that the node has failed to start and is confused about the node id it is meant to be starting with.
Identity Manager will appear to be up as some tasks will be handled by the nodes that are up.
If this happens, shutdown all the nodes and restart one by one.
Restarting the affected node alone will not resolve the issue.