(Portable) Virtual Machines
I have used VMWare Workstation and more recently VMWare Player to both allow me to run Linux and Windows on the same computer and run several instances of Linux - to keep projects seperate from each other and to allow new versions of software to be tried without damaging the main working environment.
If you have only one large machine, thats pretty much it, you can create virtual machines inside it, give them their own RAM, Hard Disk space and Network connections and if your system has enough memory and cpu speed, run several of them at a time.
Backing up any of these Virtual Systems is simply a question of copying the folder they live in onto an external disk or tape system.
For me, an extra benefit is portability, if your system fails, you can take your copies (you did make them didn’t you?) to another machine, install the VMWare software, and you are back up and running! Going off on the road for a while, copy the virtual machines to the laptop and your computing environment goes with you (although for security, a pocket hard drive might be a better place to keep all those files).
The recent versions of windows spoilt all of this by keying the running system to the hardware, not a problem, you would think, VMWare virtualises most of the hardware, but the processor type is actually passed through to the virtual machine. If your running Intel hardware, your virtual machines will see an Intel Processor - very similar to the physical processor on the mother board. If you are running an AMD system, then that is what the virtual machines will see.
For upgraders, XP used to allow several changes to the main hardware components per year before complaining and requiring the system be re-registered, possibly over the phone.
Because of this, for a really portable Virtual Machine that you could take from one system to another - and then back again if thats what was needed, you need to be running pre Windows XP or Linux.
As I happen to prefer Linux over Windows, this is not really a problem for me. I need windows software because most of the people I deal with are using it, but my documents, emails, web browsing and developement are all mainly done under Linux.
There are a couple of things that have to be considered when using Virtual Machines accross several different computers:-
First, You have to be able to transfer the Virtual Hard Drives between sytems. If you might need to do it using a network or the first portable drive you have with space on it, then you need to get VMWare to create the Virtual Drives in 2Gb segments - there is a Tickbox for this in VMWare Workstation & VMWare Server.
If you are using a third party tool to create blank images for VMWare Player, then its worth checking for the option.
Although splitting the drive into 2Gb segments may cause a slight drop performance, you are more likely to be able to transfer the resulting files using whatever network or portable drive you have to hand.
Second, when you power up the virtual machine, the host computer will need a good chunk of ram plus any ram you dedicate to the virtual system in its .ini file. To avoid having to change these settings in order to start your virtual machine, it is better to give them enough RAM to get the job done comfortably than max them out because on your main machine you can. If you have plenty of RAM, you can always run several machines at the same time!
The only problem I have with Virtual Machines is the way that their hard drives are contained. This is the only way to do it when mixing different systems (Linux/Windows), each Virtual Drive can be formatted as FAT, NTFS, EXT2, whatever, but this does mean that it is not easy to drag out the files from a Virtual Machine that has been broken, you have to add the Virtual Drive to another Virtual Machine and use that to copy the files.
Also, it is not easy (using VMWare Workstation/Player) to alter the size of the drives. I used to find that I had several large Virtual Machines/Drives taking up all of the space on my system. Quite often, I’d start working with a new software build only to find that I had under estimated the space needed.
Of course, the problem is caused by my reluctance to delete old copies (you won’t know you need it until you delete it!) and the way that VMWare (or other Virtual Machine Software) can copy a template Linux or Windows system leaving you to alter a few network settings before starting a new project.
I have recently found an answer - for Linux environments that don’t need high speed graphics, a VPS Server.
Tags: Virtual Machine, VPS