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Restore VM back from the dead with this utility

It's not often that a systems administrator gets a broken virtual machine that needs to be imported, but the recovery effort helps reinforce a few important lessons.

Recently, I had an interesting project land in my lap. I was handed a broken virtual machine (VM) with no valid...

backup on a USB stick. Could I resuscitate this dead VM? It's not a typical task for a VMware administrator, but how I was able to resolve the problem may be useful for someone who faces a similar challenge.

A little background, a Windows administrator copied the VM onto the USB drive. Due to the nature of this project, I was not able to contact this administrator for further assistance. I had to make do with what I was given. When I opened the disk, my heart sunk. It appeared to have only oneVMX file> and the flat disks that made up the drives.

Trying to install from the vSphere client

My first plan was attempt to import the files as they were. I assumed the missing files would be created if needed. I created a folder on a spare datastore and uploaded the files. I tried to import the VM with the "Add to Inventory" right click, the vSphere client refused and left behind what it deemed an orphan VM.

At this point, I thought it may well be easier to create a new VM and attach the disks. Part of the issue was that I didn't even know which operating system (OS) the VM had. A quick look into the VMX file revealed it was supposed to be a Windows 2003 server.

After uncovering the OS, I had created an empty shell, using the correct SCSI virtual hardware that now had all the required files, such as the NVRAM file and a valid VMX file. After removing the current disk and adding in the disks that had been provided to me, I was feeling optimistic and powered on the VM.

The mystery deepens

Instead of a running VM, what I got was a strange error about the virtual disk type on the machine. It refused to power on. After some Googling, I was a bit more informed about the origin of this machine and uncovered that it had been on a VMware Server. When I say VMware Server, I don't mean the ESXi hypervisor, but a legacy product that was released in 2006 and discontinued in 2010. VMware provided it as a free alternative to the full ESX package. It was essentially a type-2 hypervisor that ran in a Windows-based server that I had some experience with back when it was first released.

Can vmkfstools crack this nut?

How did I know these files were from a VMware Server box? It came down to deducing it wouldn't power on because the VMDKs were in the wrong format. To convert them to a format that works in ESXi, I had to use vmkfstools for this process. When I had finished, the file sizes had grown significantly. Again, I was hopeful.

Once I had expanded the disks, the machine came up with the message, "No boot device found, press Ctrl+Alt+Del to reboot." I was a bit puzzled, but a little more research revealed the VMware Server product used virtual IDE hard disks. ESXi has one disk option: SCSI. You can use IDE devices in ESXi but only to boot media, such as CD-ROM. This put me in a Catch-22 situation: I was unable to boot the disk to install the drivers required for the VM to boot under ESXi, but I couldn't get the drivers added because it wouldn't boot.

Letting VMware Converter take a shot

At this point, I was close to giving up, but a colleague suggested using VMware converter, which is a tool for importing VMs from other virtualization platforms. I didn't have high hopes.

After several hours of processing, VMware Converter finished and, to my sheer amazement, I was able to import the VM and get it to boot.

To be honest, I am a systems administrator who prefers to use the command line, but I have a new respect for VMware Converter. It's a very helpful utility that has many options I didn't know existed.

Lessons learned

While frustrating at times, this resurrection exercise was helpful in producing a few insights.

First, anyone using a hypervisor product that has been phased out should switch to one that is still actively supported. VMware Server was free, but so is ESXi for a one-socket machine. The performance of ESXi on bare metal is significantly faster than what VMware Server can muster.

Second, I now know VMware Converter is a powerful tool that could come in handy if I ever run into any older VMs that won't import properly.

Lastly, it's a lesson to all of us that the longer an environment is left on outdated software, the more expensive and complicated it becomes to maintain and eventually migrate.

Next Steps

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