I am geting error when try do a snapshot:

Error msg in SPM log.

2018-05-02 17:46:11,235-0300 WARN  (tasks/2) [storage.ResourceManager] Resource factory failed to create resource '01_img_6e5cce71-3438-4045-9d54-607123e0557e.ed7f1c0f-5986-4979-b783-5c465b0854c6'. Canceling request. (resourceManager:543)

Traceback (most recent call last):

  File "/usr/lib/python2.7/site-packages/vdsm/storage/resourceManager.py", line 539, in registerResource

    obj = namespaceObj.factory.createResource(name, lockType)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/resourceFactories.py", line 193, in createResource

    lockType)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/resourceFactories.py", line 122, in __getResourceCandidatesList

    imgUUID=resourceName)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/image.py", line 213, in getChain

    if srcVol.isLeaf():

  File "/usr/lib/python2.7/site-packages/vdsm/storage/volume.py", line 1430, in isLeaf

    return self._manifest.isLeaf()

  File "/usr/lib/python2.7/site-packages/vdsm/storage/volume.py", line 138, in isLeaf

    return self.getVolType() == sc.type2name(sc.LEAF_VOL)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/volume.py", line 134, in getVolType

    self.voltype = self.getMetaParam(sc.VOLTYPE)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/volume.py", line 118, in getMetaParam

    meta = self.getMetadata()

  File "/usr/lib/python2.7/site-packages/vdsm/storage/blockVolume.py", line 112, in getMetadata

    md = VolumeMetadata.from_lines(lines)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/volumemetadata.py", line 103, in from_lines

    "Missing metadata key: %s: found: %s" % (e, md))

MetaDataKeyNotFoundError: Meta Data key not found error: ("Missing metadata key: 'DOMAIN': found: {'NONE': '######################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################'}",)

2018-05-02 17:46:11,286-0300 WARN  (tasks/2) [storage.ResourceManager.Request] (ResName='01_img_6e5cce71-3438-4045-9d54-607123e0557e.ed7f1c0f-5986-4979-b783-5c465b0854c6', ReqID='a3cd9388-977b-45b9-9aa0-e431aeff8750') Tried to cancel a processed request (resourceManager:187)

2018-05-02 17:46:11,286-0300 ERROR (tasks/2) [storage.TaskManager.Task] (Task='ba0766ca-08a1-4d65-a4e9-1e0171939037') Unexpected error (task:875)

Traceback (most recent call last):

  File "/usr/lib/python2.7/site-packages/vdsm/storage/task.py", line 882, in _run

    return fn(*args, **kargs)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/task.py", line 336, in run

    return self.cmd(*self.argslist, **self.argsdict)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/securable.py", line 79, in wrapper

    return method(self, *args, **kwargs)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/sp.py", line 1938, in createVolume

    with rm.acquireResource(img_ns, imgUUID, rm.EXCLUSIVE):

  File "/usr/lib/python2.7/site-packages/vdsm/storage/resourceManager.py", line 1025, in acquireResource

    return _manager.acquireResource(namespace, name, lockType, timeout=timeout)

  File "/usr/lib/python2.7/site-packages/vdsm/storage/resourceManager.py", line 475, in acquireResource

    raise se.ResourceAcqusitionFailed()

ResourceAcqusitionFailed: Could not acquire resource. Probably resource factory threw an exception.: ()

Anyone help?