Article ID: 118276, created on Oct 29, 2013, last review on Jun 17, 2016

  • Applies to:
  • Virtuozzo
  • Virtuozzo hypervisor


All virtual machines on Parallels Server Bare Metal 5.0 are configured to start automatically after node reboot, however sometimes a virtual machine does not start automatically after I reboot the host.

After host reboot, the first event I see in the parallels.log file inside the virtual machine's directory (usually, /var/parallels/<VM_NAME>.pvm/parallels.log) - is "Unmerged backup snapshot found":

09-12 13:53:33.214 F /disp:3844:fbdc8760/ Unmerged backup snapshot found for Vm {de2dc169-e18d-493f-ac1d-2efad4208a90}
09-12 13:53:33.277 F /disp:3844:f1f9c700/ Vm state was changed from VMS_STOPPED to VMS_DELETING_STATE for vm {de2dc169-e18d-493f-ac1d-2efad4208a90} (name='MyVM')
09-12 13:53:33.511 F /virtuozzo:3844:fbdc8760/ uuid={de2dc169-e18d-493f-ac1d-2efad4208a90} id=1774267870
09-12 13:53:33.769 F /disp:3844:d3fff700/ AUTOSTART_OPTION {de2dc169-e18d-493f-ac1d-2efad4208a90} MyVM: 2 : 3
09-12 13:53:33.769 F /disp:3844:d3fff700/ isLastRunningState {de2dc169-e18d-493f-ac1d-2efad4208a90} MyVM: 1
09-12 14:11:30.563 F /disp:3844:f159b700/ Recieved event PET_DSP_EVT_VM_STOPPED (100008) from vm {de2dc169-e18d-493f-ac1d-2efad4208a90} (name='MyVM')
09-12 14:11:30.573 F /disp:3844:f159b700/ Vm state was changed from VMS_DELETING_STATE to VMS_STOPPING for vm {de2dc169-e18d-493f-ac1d-2efad4208a90} (name='MyVM')
09-12 14:11:30.756 F /disp:3844:f1f9c700/ Vm state was changed from VMS_STOPPING to VMS_STOPPED for vm {de2dc169-e18d-493f-ac1d-2efad4208a90} (name='MyVM')


If host reboot takes place while snapshot is being deleted - such virtual machine will ignore the auto-start setting and such virtual machine is to be started manually.


For PSBM 5.0 installations, the issue is addressed as per the request PSBM-22278 and the fix is available in Parallels Server Bare Metal 5.0 update 10.

Additionally, the problem does not exist in Parallels Cloud Server 6.0 since Update 4 (6.0.0-1619).

It is possible to upgrade Parallels Server Bare Metal to Parallels Cloud Server according to the Upgrading to PCS Guide.

Also see

About Parallels Cloud Server:

If the server hosts containers:

  • 115479 How to convert VZFS4 containers to ploop format.

Search Words



Unmerged backup snapshot found

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