[ovirt-users] adding glusterfs to ovirt

I installed a oVirt stack without glusterfs. Now I want to add it. So I configured a cluster to be a gluster-enabled one. Now i want to add a gluster volume to it. That went fine until I click Ok at the "New Volume" dialog, the answer was : Error while executing action Create Gluster Volume: Unexpected exception I the log, I saw : 2016-04-13 16:45:53,573 INFO [org.ovirt.engine.core.vdsbroker.gluster.GlusterTasksListVDSCommand] (DefaultQuartzScheduler_Worker-84) [5303bffb] FINISH, GlusterTasksListVDSCommand, log id: 2e5a7991 2016-04-13 16:45:53,573 ERROR [org.ovirt.engine.core.bll.gluster.GlusterTasksSyncJob] (DefaultQuartzScheduler_Worker-84) [5303bffb] Error updating tasks from CLI: org.ovirt.engine.core.common.errors.EngineException: EngineException: org.ovirt.engine.core.vdsbroker.vdsbroker.VDSErrorException: VDSGenericException: VDSErrorException: Failed to GlusterTasksListVDS, error = The method does not exist / is not available., code = -32601 (Failed with error unexpected and code 16) at org.ovirt.engine.core.bll.VdsHandler.handleVdsResult(VdsHandler.java:112) [bll.jar:] at org.ovirt.engine.core.bll.VDSBrokerFrontendImpl.RunVdsCommand(VDSBrokerFrontendImpl.java:33) [bll.jar:] at org.ovirt.engine.core.bll.gluster.tasks.GlusterTasksService.runVdsCommand(GlusterTasksService.java:64) [bll.jar:] at org.ovirt.engine.core.bll.gluster.tasks.GlusterTasksService.getTaskListForCluster(GlusterTasksService.java:32) [bll.jar:] at org.ovirt.engine.core.bll.gluster.GlusterTasksSyncJob.updateGlusterAsyncTasks(GlusterTasksSyncJob.java:87) [bll.jar:] at sun.reflect.GeneratedMethodAccessor250.invoke(Unknown Source) [:1.7.0_99] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_99] at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_99] at org.ovirt.engine.core.utils.timer.JobWrapper.invokeMethod(JobWrapper.java:81) [scheduler.jar:] at org.ovirt.engine.core.utils.timer.JobWrapper.execute(JobWrapper.java:52) [scheduler.jar:] at org.quartz.core.JobRunShell.run(JobRunShell.java:213) [quartz.jar:] at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:557) [quartz.jar:]