Some time ago I managed to isolate an ugly vSphere 5 bug that caused me some unpleasant moments. Today I finally reproduced this behavior in a clean lab environment, so I feel confident enough to describe it in public. Don’t worry, the way to recover is described also!
Take a vSphere 5 environment with a template (say, “MyTemplate”) that you want to deploy a virtual machine from. Step through a regular deployment wizard and select “Edit Virtual Hardware” on the last page. In the VM properties, choose the hard disk and change its size. The new VM (say, “MyVM”) will be created successfully, but the next time you’ll go through the deployment process it will fail with a strange message: “Unable to access file ‘MyTemplate/MyTemplate.vmdk’ since it is locked”…
A quick search in VMware KB (or just in Google) will tell you that the vmdk (the virtual disk of the VM) is usually locked when some other VM uses the same disk. Hey, this is a template! No other VMs are supposed to use the template disk, right? Well, the truth is that this disk is now attached to MyVM – yes, that one with different disk size… But let the lock alone. Your lovely template is now gone, since the disk that belonged to the template is now owned by the running virtual machine – with new name, settings and maybe even software!
Well, how do you recover from this situation? The good news are that the original disk from MyTemplate is not gone. In fact, vSphere really cloned a new vmdk file for MyVM and placed it where it should usually reside – in ‘MyVM/MyVM.vmdk’ – but for some reason set the MyVM to use a template file instead. At this moment you can take a deep breath, shut down MyVM, point it to the right virtual disk and physically swap the files in the datastore… Continue reading “Deployment of New VM from Template Fails with VMDK Locked Error” →