Virtual Machine Musings

Recently at work we were given a .OVA file to play around and test with. Turns out OVA stands for “Open Virtual Appliance” and is basically a file that allows for easy deployment of pre-packaged Virtual Machines (VMs).

I had three options to run this OVA:
1. Use a pre-existing installation of the free VMWare Server
2. Use a pre-exisitng installation of the free, open source Virtual-Box
3. Download and use the free VMWare ESXi server

The ESXi option was the most alluring. It is basically an iso image that can be used to convert a 64-bit server (32 bit servers need a previous version, its no longer supported) into a “hypervisor”, that is, a server which is dedicated to running just VMs. There is more info here https://www.vmware.com/products/esxi/

Not having the necessary hardware to run it, we decided to try run the ESXi server within another VM from VMWare Server. Note this is never good for production, there is such a thing as too much virtualization, and having a VM within a VM is not a good idea. The installation went pretty smooth, no error and simple enough configuration, just a couple of IP address and DNS details. Once installed and customized, you can access the ESX server over using http://%5Bip_address%5D. This brings you to a download page which offers the option of installing VMWare vSphere. I wasnt a fan of this simply because its a paid product. Fortunately VMWare has release a nice freebie they dubbed “VMWare GO”. Its a hybrid desktop / web application that once installed allows you to administer the ESX server in a clean and simple manner. https://go.vmware.com/default2.aspx. It took only a couple of minutes to import the OVA file using VMWare GO to the ESX server and get the image up and running.

Next I turned my attention to importing the OVA file to be used by VMWare server. Again, with the proper tools this was easy. VMWare provides another usefull freebe called VMWare vCentre Standalone Converter. This program allows not only the conversion of .OVA files into .vmx for use with VMWare server, it also converts physical machines into VMs, and so on. For my pruposes I simply clicked on “Convert Machine” on the top left, and selected source type as “Virtual Appliance”. Two clicks later, I selected the destination as being “VMWare Workstation or other VMWare virtual machine”. Once it completed, from VMWare server I slected to import an existing VM and that was it… up and running🙂

Last but not least, I am a fan of open source Virtual Box, I think its slightly better than VMWare. So I wanted to open this file on from Virtual Box. Some research led me to find out that actually the OVA file in an archive which bundles the VM config file (OVF) the RAMDISK and HardDISK image of the VM together. So I opened the OVA file in 7zip and indeed we get three files including a .ovf and .vmdk. The OVF file can be imported very simply using Virtual Box, simply by using File > Import Aplliance and following the wizard. Two minutes later, the VMWare image was up and running.