[Users] Can't delete snapshot

Hi friends! I'm trying delete a snapshot but webadmin returns me: "Failed to complete Snapshot bla deletion on VM piromba.dem.inpe.br." In vdsm.log of SPM, I got: Oct 10 16:24:10 newton kernel: end_request: I/O error, dev dm-24, sector 2147483632 Oct 10 16:24:10 newton kernel: end_request: I/O error, dev dm-24, sector 0 Oct 10 16:24:11 newton kernel: end_request: I/O error, dev dm-24, sector 2147483520 Oct 10 16:24:11 newton kernel: end_request: I/O error, dev dm-24, sector 2147483632 Oct 10 16:24:11 newton kernel: end_request: I/O error, dev dm-24, sector 0 Oct 10 16:24:11 newton kernel: end_request: I/O error, dev dm-24, sector 2147483520 Oct 10 16:24:11 newton kernel: end_request: I/O error, dev dm-24, sector 2147483632 Oct 10 16:24:11 newton kernel: end_request: I/O error, dev dm-24, sector 0 Oct 10 16:24:12 newton vdsm TaskManager.Task ERROR Task=`767206b3-87e9-4686-b06c-6fba24bdb677`::Unexpected error#012Traceback (most recent call last):#012 File "/usr/share/vdsm/storage/task.py", line 861, in _run#012 return fn(*args, **kargs)#012 File "/usr/share/vdsm/storage/task.py", line 320, in run#012 return self.cmd(*self.argslist, **self.argsdict)#012 File "/usr/share/vdsm/storage/securable.py", line 63, in wrapper#012 return f(self, *args, **kwargs)#012 File "/usr/share/vdsm/storage/sp.py", line 1786, in mergeSnapshots#012 image.Image(repoPath).merge(sdUUID, vmUUID, imgUUID, ancestor, successor, postZero)#012 File "/usr/share/vdsm/storage/image.py", line 1084, in merge#012 allVols = sdDom.getAllVolumes()#012 File "/usr/share/vdsm/storage/blockSD.py", line 869, in getAllVolumes#012 return getAllVolumes(self.sdUUID)#012 File "/usr/share/vdsm/storage/blockSD.py", line 168, in getAllVolumes#012 and vImg not in res[vPar]['imgs']:#012KeyError: '63650a24-7e83-4c0a-851d-0ce9869a294d' [root@newton ~]# ls -l /dev/mapper/ total 0 lrwxrwxrwx. 1 root root 8 Oct 8 17:34 1IET_00010001 -> ../dm-24 Anyone knows what is this device? Thanks.