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 one VMX 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.
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.
The pros and cons of various VMware data backup and restore methods