Thanks Gobinda and Parth.

I followed what indicated by Gobinda:

[root@ovirt ~]# ovirt-hosted-engine-cleanup -q
  -=== Destroy hosted-engine VM ===-
You must run deploy first
  -=== Killing left-behind HostedEngine processes ===-
/sbin/ovirt-hosted-engine-cleanup: line 57: kill: (18988) - No such process
error: failed to get domain 'HostedEngine'

  -=== Stop HA services ===-
  -=== Shutdown sanlock ===-
shutdown force 1 wait 0
shutdown done 0
  -=== Disconnecting the hosted-engine storage domain ===-
You must run deploy first
  -=== De-configure VDSM networks ===-
ovirtmgmt
ovirtmgmt
  -=== Stop other services ===-
Warning: Stopping libvirtd.service, but it can still be activated by:
  libvirtd-admin.socket
  libvirtd.socket
  libvirtd-ro.socket
  -=== De-configure external daemons ===-
Removing database file /var/lib/vdsm/storage/managedvolume.db
  -=== Removing configuration files ===-
? /etc/init/libvirtd.conf already missing
- removing /etc/libvirt/nwfilter/vdsm-no-mac-spoofing.xml
? /etc/ovirt-hosted-engine/answers.conf already missing
? /etc/ovirt-hosted-engine/hosted-engine.conf already missing
- removing /etc/vdsm/vdsm.conf
- removing /etc/pki/vdsm/certs/cacert.pem
- removing /etc/pki/vdsm/certs/vdsmcert.pem
- removing /etc/pki/vdsm/keys/vdsmkey.pem
- removing /etc/pki/vdsm/libvirt-migrate/ca-cert.pem
- removing /etc/pki/vdsm/libvirt-migrate/server-cert.pem
- removing /etc/pki/vdsm/libvirt-migrate/server-key.pem
- removing /etc/pki/vdsm/libvirt-spice/ca-cert.pem
- removing /etc/pki/vdsm/libvirt-spice/server-cert.pem
- removing /etc/pki/vdsm/libvirt-spice/server-key.pem
- removing /etc/pki/vdsm/libvirt-vnc/ca-cert.pem
- removing /etc/pki/vdsm/libvirt-vnc/server-cert.pem
- removing /etc/pki/vdsm/libvirt-vnc/server-key.pem
- removing /etc/pki/CA/cacert.pem
- removing /etc/pki/libvirt/clientcert.pem
- removing /etc/pki/libvirt/private/clientkey.pem
? /etc/pki/ovirt-vmconsole/*.pem already missing
- removing /var/cache/libvirt/qemu
? /var/run/ovirt-hosted-engine-ha/* already missing
? /var/tmp/localvm* already missing
  -=== Removing IP Rules ===-
[root@ovirt ~]#

Then I executed the hosted engine setup from the wizard and chose Gluster as the shared storage and all worked ok.

Now I have the final engine up and the 3 storage domains active.

The only strange thing I see is that on the host the volumes are active (obviously ;-) but in ovirt web admin gui the storage -> volumes page is empty.

[root@ovirt ~]# gluster volume list
data
engine
vmstore

[root@ovirt ~]# gluster volume status engine
Status of volume: engine
Gluster process                             TCP Port  RDMA Port  Online  Pid
------------------------------------------------------------------------------
Brick ovirtst.righini.storage:/gluster_bric
ks/engine/engine                            49152     0          Y       12947
 
Task Status of Volume engine
------------------------------------------------------------------------------
There are no active volume tasks
 
[root@ovirt ~]# gluster volume status data
Status of volume: data
Gluster process                             TCP Port  RDMA Port  Online  Pid
------------------------------------------------------------------------------
Brick ovirtst.righini.storage:/gluster_bric
ks/data/data                                49153     0          Y       13195
 
Task Status of Volume data
------------------------------------------------------------------------------
There are no active volume tasks
 
[root@ovirt ~]# gluster volume status vmstore
Status of volume: vmstore
Gluster process                             TCP Port  RDMA Port  Online  Pid
------------------------------------------------------------------------------
Brick ovirtst.righini.storage:/gluster_bric
ks/vmstore/vmstore                          49154     0          Y       13447
 
Task Status of Volume vmstore
------------------------------------------------------------------------------
There are no active volume tasks
 
[root@ovirt ~]#

[root@ovirt ~]# df -h | egrep "Size|rhev"
Filesystem                                         Size  Used Avail Use% Mounted on
ovirtst.mydomain.storage:/engine                    100G  8.6G   92G   9% /rhev/data-center/mnt/glusterSD/ovirtst.mydomain.storage:_engine
ovirtst.mydomain.storage:/data                      300G  5.2G  295G   2% /rhev/data-center/mnt/glusterSD/ovirtst.mydomain.storage:_data
ovirtst.mydomain.storage:/vmstore                   200G  3.5G  197G   2% /rhev/data-center/mnt/glusterSD/ovirtst.mydomain.storage:_vmstore
[root@ovirt ~]#

domains:

volumes:

Is there anything to enable to have the volumes visible?

Gianluca