One process that I killed was: [root@ovirt-node4 ~]# ps axuww | grep qemu-nbd vdsm 588156 0.0 0.0 308192 39840 ? Ssl Aug26 0:12 /usr/bin/qemu-nbd --socket /run/vdsm/nbd/c7653559-508b-4e4a-a591-32dec3e5a29d.sock --persistent --shared=8 --export-name= --cache=none --aio=native --allocation-depth --read-only json:{"driver": "qcow2", "file": {"driver": "file", "filename": "/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/7a05ff72-370e-4d0c-ab56-5f161cc98318/52ee7e19-ac78-4c05-81e2-0c75dad71732"}} The event that was talking about "file lock" is this in the engine.log: 2022-08-31 10:39:16,431Z INFO [org.ovirt.engine.core.vdsbroker.vdsbroker.GetHostJobsVDSCommand] (EE-ManagedScheduledExecutorService-engineScheduledThreadPool-Thread-91) [617f02f1-29e6-45f4-b5bc-aa4c16b02b15] FINISH, Ge tHostJobsVDSCommand, return: {667f22f0-3df5-43b8-b94d-c0ee48424247=HostJobInfo:{id='667f22f0-3df5-43b8-b94d-c0ee48424247', type='storage', description='merge_subchain', status='failed', progress='0', error='VDSError:{co de='GeneralException', message='General Exception: ('Command [\'/usr/bin/qemu-img\', \'commit\', \'-p\', \'-t\', \'none\', \'-b\', \'/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/im ages/7a05ff72-370e-4d0c-ab56-5f161cc98318/d0e6f4b9-ae29-493d-b22f-c6aee55d84ae\', \'-f\', \'qcow2\', \'/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/7a05ff72-370e-4d0c-ab56-5 f161cc98318/52ee7e19-ac78-4c05-81e2-0c75dad71732\'] failed with rc=1 out=b\'\' err=bytearray(b\'qemu-img: Could not open \\\'/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/7a0 5ff72-370e-4d0c-ab56-5f161cc98318/52ee7e19-ac78-4c05-81e2-0c75dad71732\\\': Failed to get "write" lock\\nIs another process using the image [/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b1 00d72/images/7a05ff72-370e-4d0c-ab56-5f161cc98318/52ee7e19-ac78-4c05-81e2-0c75dad71732]?\\n\')',)'}'}}, log id: 2c62cd00 so these are the logs related to this qemu-nbd command invocation: https://cloud.ssis.sm/index.php/s/RSpQJHEeDxai5ea The other qemu-nbd: [root@ovirt-node3 ~]# ps -ef | grep qemu-nbd vdsm 1795830 1 0 Aug26 ? 00:00:09 /usr/bin/qemu-nbd --socket /run/vdsm/nbd/54097389-db69-4aa3-a34d-eb6cb2c1fc4b.sock --persistent --shared=8 --export-name= --cache=none --aio=native --allocation-depth --read-only json:{"driver": "qcow2", "file": {"driver": "file", "filename": "/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/5d18a058-652f-4c94-a9ff-9c15152c61b4/f17c3443-b62f-43f5-b35c-5ba9225abaf4"}} The engine.log lock event: 2022-08-31 10:23:54,033Z INFO [org.ovirt.engine.core.vdsbroker.vdsbroker.GetHostJobsVDSCommand] (EE-ManagedScheduledExecutorService-engineScheduledThreadPool-Thread-91) [4a3cf96d-5fb8-4479-9eda-4012d1cae8c2] FINISH, GetHostJobsVDSCommand, return: {f0df76ab-c708-4c0f-ad8e-ecf26c8910d9=HostJobInfo:{id='f0df76ab-c708-4c0f-ad8e-ecf26c8910d9', type='storage', description='merge_subchain', status='failed', progress='0', error='VDSError:{code='GeneralException', message='General Exception: ('Command [\'/usr/bin/qemu-img\', \'commit\', \'-p\', \'-t\', \'none\', \'-b\', \'/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/5d18a058-652f-4c94-a9ff-9c15152c61b4/f17c3443-b62f-43f5-b35c-5ba9225abaf4\', \'-f\', \'qcow2\', \'/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/5d18a058-652f-4c94-a9ff-9c15152c61b4/98ddfc07-8d97-4511-bfef-1ea0ce72b5a6\'] failed with rc=1 out=b\'\' err=bytearray(b\'qemu-img: Failed to get "w rite" lock\\nIs another process using the image [/rhev/data-center/mnt/glusterSD/localhost:_gv0/60b7f172-08ed-4a22-8414-31fd5b100d72/images/5d18a058-652f-4c94-a9ff-9c15152c61b4/f17c3443-b62f-43f5-b35c-5ba9225abaf4]?\\n\')',)'}'}}, log id: 380108e6 and these are related log: https://cloud.ssis.sm/index.php/s/p3LAAkXxRrAbdxK