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Unable to poweron the VM. (Failed to lock the file)



I have encountered may issues like where after some upgrade or migration we were unable to power on the VM.

Figure 1
An error was received from the ESX host while powering on VM HSSVSQL01.
Failed to start the virtual machine.
Cannot open the disk '/vmfs/volumes/578d835c-18b2c97a-9b0d-0025b5f13920/SAMPLE1_cloud/000000.vmdk' or one of the snapshot disks it depends on.


Failed to lock the file

In above Figure:1, where while powering on the VM, its prompt for an error.

Well, there are several reason for where the VM unable to poweron and you can find many article on this.

Here in this article we will discuss to resolve this issue.

Please use below step to resolve the disk lock issue




  •  Checked that VM is running on snapshot if its getting error " VM Consolidation required".


  • Checked the snapshot manager if its showing any snapshot. If yes, try to delete the  snapshot.


  • Verified the same from Esxi cli to identify whether it has delta files are located on all or some of the disks.


  • Checked the consistency of the .vmdk file by using "vmkfstools -D /vmfs/volumes/.vmdk"


  • Disk consistency can also be checked from below command


     (find . -name \*.vmdk -size -10k | xargs egrep -i "CID|PID" | sort -n) This is a nice
     command which you can run inside the VM folder to check the consistency against CID
     and PID of the .VMDK files.


  • Verified by using touch command to VMDK " touch abcdefgh.vmdk to verify if there is any lock on the .VMDK.

  • Verified the snapshot from the Esxcli by using "vim-cmd vmsvc/snapshot.get (VMID)

  • If unable to find any snapshot available from the output but in actual there are snapshot on the VM.
  • Tried to delete the snapshot from the VM by using vim-cmd vmsvc/snapshot.removeall (vmid)

  • Checked the .ctk files under vm directory and move all the .ctk.vmdk files to other folder i.e (Temp folder)

  • Try cloning all the .vmdk base disk as the last snapshot disks are getting error of "failed to lock the file. If last snapshot files unable to create the clone drive, try cloning next above to that. Here in this case if any of the snapshot disk failes to take snapshot , there are chances to loose the data. Verify by using df -h to verify the .delta.vmdk disk size, if its less then 16 MB then there are rare chances to loose the data, but ifs more than that then chances of loosing data from snapshot disk is quite higher.

          Use below command to clone the snaphot file or base file of the .vmdk

        vmkfstools -i TEST01.vmdk vmfs/volumes/578d835c-18b2c97a-9b0d-
        0025b5f13920/SAMPLE1_cloud/000000.vmdk -d thin
  •  After cloning all the VM, attached all the disks to the VM, and now able to power on all the VM without any issue.


Happy Sharing.... :)



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