Some interesting output from the vdsm log...


2017-02-09 15:16:24,051 INFO  (jsonrpc/1) [storage.StorageDomain] Resource namespace 01_img_60455567-ad30-42e3-a9df-62fe86c7fd25 already registered (sd:731)
2017-02-09 15:16:24,051 INFO  (jsonrpc/1) [storage.StorageDomain] Resource namespace 02_vol_60455567-ad30-42e3-a9df-62fe86c7fd25 already registered (sd:740)
2017-02-09 15:16:24,052 INFO  (jsonrpc/1) [storage.SANLock] Acquiring Lease(name='SDM', path=u'/rhev/data-center/mnt/glusterSD/localhost:data2/60455567-ad30-42e3-a9df-6
2fe86c7fd25/dom_md/leases', offset=1048576) for host id 1 (clusterlock:343)
2017-02-09 15:16:24,057 INFO  (jsonrpc/1) [storage.SANLock] Releasing host id for domain 60455567-ad30-42e3-a9df-62fe86c7fd25 (id: 1) (clusterlock:305)
2017-02-09 15:16:25,149 INFO  (jsonrpc/3) [jsonrpc.JsonRpcServer] RPC call GlusterHost.list succeeded in 0.17 seconds (__init__:515)
2017-02-09 15:16:25,264 INFO  (Reactor thread) [ProtocolDetector.AcceptorImpl] Accepted connection from ::ffff:127.0.0.1:55060 (protocoldetector:72)
2017-02-09 15:16:25,270 INFO  (Reactor thread) [ProtocolDetector.Detector] Detected protocol stomp from ::ffff:127.0.0.1:55060 (protocoldetector:127)
2017-02-09 15:16:25,271 INFO  (Reactor thread) [Broker.StompAdapter] Processing CONNECT request (stompreactor:102)
2017-02-09 15:16:25,271 INFO  (JsonRpc (StompReactor)) [Broker.StompAdapter] Subscribe command received (stompreactor:129)
2017-02-09 15:16:25,416 INFO  (jsonrpc/5) [jsonrpc.JsonRpcServer] RPC call Host.getHardwareInfo succeeded in 0.01 seconds (__init__:515)
2017-02-09 15:16:25,419 INFO  (jsonrpc/6) [dispatcher] Run and protect: repoStats(options=None) (logUtils:49)
2017-02-09 15:16:25,419 INFO  (jsonrpc/6) [dispatcher] Run and protect: repoStats, Return response: {u'e8d04da7-ad3d-4227-a45d-b5a29b2f43e5': {'code': 0, 'actual': True
, 'version': 4, 'acquired': True, 'delay': '0.000854128', 'lastCheck': '5.1', 'valid': True}, u'a77b8821-ff19-4d17-a3ce-a6c3a69436d5': {'code': 0, 'actual': True, 'vers
ion': 4, 'acquired': True, 'delay': '0.000966556', 'lastCheck': '2.6', 'valid': True}} (logUtils:52)
2017-02-09 15:16:25,447 INFO  (jsonrpc/6) [jsonrpc.JsonRpcServer] RPC call Host.getStats succeeded in 0.03 seconds (__init__:515)
2017-02-09 15:16:25,450 ERROR (JsonRpc (StompReactor)) [vds.dispatcher] SSL error receiving from <yajsonrpc.betterAsyncore.Dispatcher connected ('::ffff:127.0.0.1', 55060, 0, 0) at 0x7f69c0043cf8>: unexpected eof (betterAsyncore:113)
2017-02-09 15:16:25,812 INFO  (jsonrpc/7) [jsonrpc.JsonRpcServer] RPC call GlusterVolume.list succeeded in 0.10 seconds (__init__:515)
2017-02-09 15:16:25,940 INFO  (Reactor thread) [ProtocolDetector.AcceptorImpl] Accepted connection from ::ffff:127.0.0.1:55062 (protocoldetector:72)
2017-02-09 15:16:25,946 INFO  (Reactor thread) [ProtocolDetector.Detector] Detected protocol stomp from ::ffff:127.0.0.1:55062 (protocoldetector:127)
2017-02-09 15:16:25,947 INFO  (Reactor thread) [Broker.StompAdapter] Processing CONNECT request (stompreactor:102)
2017-02-09 15:16:25,947 INFO  (JsonRpc (StompReactor)) [Broker.StompAdapter] Subscribe command received (stompreactor:129)
2017-02-09 15:16:26,058 ERROR (jsonrpc/1) [storage.TaskManager.Task] (Task='02cad901-5fe8-4f2d-895b-14184f67feab') Unexpected error (task:870)
Traceback (most recent call last):
  File "/usr/share/vdsm/storage/task.py", line 877, in _run
    return fn(*args, **kargs)
  File "/usr/lib/python2.7/site-packages/vdsm/logUtils.py", line 50, in wrapper
    res = f(*args, **kwargs)
  File "/usr/share/vdsm/storage/hsm.py", line 812, in forcedDetachStorageDomain
    self._deatchStorageDomainFromOldPools(sdUUID)
  File "/usr/share/vdsm/storage/hsm.py", line 790, in _deatchStorageDomainFromOldPools
    dom.acquireClusterLock(host_id)
  File "/usr/share/vdsm/storage/sd.py", line 810, in acquireClusterLock
    self._manifest.acquireDomainLock(hostID)
  File "/usr/share/vdsm/storage/sd.py", line 499, in acquireDomainLock
    self._domainLock.acquire(hostID, self.getDomainLease())
  File "/usr/lib/python2.7/site-packages/vdsm/storage/clusterlock.py", line 362, in acquire
    "Cannot acquire %s" % (lease,), str(e))
AcquireLockFailure: Cannot obtain lock: u"id=60455567-ad30-42e3-a9df-62fe86c7fd25, rc=5, out=Cannot acquire Lease(name='SDM', path=u'/rhev/data-center/mnt/glusterSD/localhost:data2/60455567-ad30-42e3-a9df-62fe86c7fd25/dom_md/leases', offset=1048576), err=(5, 'Sanlock resource not acquired', 'Input/output error')"
2017-02-09 15:16:26,058 INFO  (jsonrpc/1) [storage.TaskManager.Task] (Task='02cad901-5fe8-4f2d-895b-14184f67feab') aborting: Task is aborted: 'Cannot obtain lock' - code 651 (task:1175)