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Showing posts from February, 2021

Virtual Machine cloning fails with error: Unable to access -000001.vmdk.ctk

    Symptoms You are unable to access a VM that has has a snapshot from the GUI. When trying to clone the VM using  vmkfstools -i sourefile.vmdk destinationfile.vmdk , you see an error like this: Unable to power on virtual machine <vm name>. Unable to access <vm name>-000001.vmdk.ctk changed-block-tracking Resolution Caution : You can easily lose data if you make a mistake while editing the .vmdk file. VMware recommends backing up your data before attempting these steps. The safest way to deal with this issue is to disable Changed Block Tracking and to try the operation again. For more information, see  Changed Block Tracking (CBT) on virtual machines (1020128) . To work around this issue, edit the snapshot's .vmdk file and place a # in front of the file reference to the .ctk file. This comments out the reference to the .ctk file, and makes it seem as though change tracking has been disabled. This prevent change tracking, but allows you to clone or otherwise access the