Virualization

[DragonPoet]

So... what is it? What are the pros and cons? Thanks for the help!

 

[Darician]

In a nutshell, it essentially is a completely isolated operating system installation within your normal operating system. Applications such as VMware Workstation and Oracle VirtualBox can accomplish this quite easily allowing you to run multiple other operating systems while still running your base OS to allow you to test and manipulate the virtual instances as you see fit.

In terms of advantages and disadvantages, it depends on what you're using virtualization for. Generally, the advantages are that Virtual Machines (VMs) can be easily moved and backed up, they can be frozen in a state and restored for testing purposes, they save power as they allow you to utilize more of one machine instead of having multiple PCs running, and additionally, they can run while you continue to use your host OS (with Workstation and VirtualBox). Disadvantages are they take up resources on your PC, you have to account for disk I/O as if you try to run multiple VMs off of one hard drive it will slow down drastically, and also they are not as fast as having an operating system running on the native hardware of a PC as they are abstracted and isolated from the real hardware. This entry explains it more in detail: Virtual machine - Wikipedia, the free encyclopedia

Again, it depends on what you need to use it for that you'll find it appropriate or not.

 

[pparks1]

As said above, advantages are better utilization of hardware. With genuine server class hardware, you can run 5-15 servers on one piece of equipment and the performance is going to be 90% as good as it would have been on standalone hardware in most instances.

For personal use, I use it heavily for testing. No sense in installing junk on my "real" machine that I want to test out and evaluate. I do it all in a virtual machine. In addition, its great for learning and testing. You can install a whole new OS and easily blow it up and build it again without taking out your actual machine. It's completely eliminated my need for dual booting anything. It easily allows you to setup a small virtual network of a handful of machines to test things like backup and restore and disaster recovery situations. And it helps immensely getting hands on experience with products that you might be studying for certifications and job experience, etc.

 

[jimbo45]

Hi there
another VERY useful use for VM's (in fact for a some people could be the only real use) is that you can often run LEGACY hardware such as older printers / plotters / scanners etc on a previous OS such as XP or Windows 2000 -- so you don't have to chuck away good serviceable hardware. Same with some software applications - where the application is still fine but the original developers no longer exist and any possible replacement is either too complex or too expensive OR BOTH.

I still copy "Virtual CD" music to a Minidisc recorder via an application that will only run up to XP or W2K3 server. I'm afraid the basic quality of current compressed MP3 music doesn't cut it for me -- I might be an old Dinosaur but the quality of recording you can get on a portable minidisc just blows an Ipod away in the dust - and you can get up to 7 hrs at high quality on an Hi-MD minidisc.

Other uses have been mentioned by previous posters such as using VM's as a "Sandbox" for testing / developing software.

Incidentally even entry level SERVER class machines are becoming affordable for home users (you can get a good basic entry level Lenovo Thinkserver for around 450 USD).

A great efficient way also is to use something like vmware's esxi or equivalent program to set up a virtual file / email / printserver (could be Linux, W2K3, W2K8 or Windows Home server etc) which is robust and efficient enough for home / small office use. With the latest "Hypervisor" type OS installed on the server almost NO resources are taken by the "Host" OS -- and as pparks said the Virtual server will run at around 90% of the native speed -- maybe as much as 95% if you have enough memory and decent disks in your Server.

If you are serious with VM's then while vmware workstation is great on a laptop for testing you really will need a decent desktop computer with at least 4 GB RAM and a dual core cpu.

However a SERVER class of machine is far far better for this type of stuff which is why I recommended something like the Lenovo thinkserver -- as it is also compatable with ESXi.
Cheers

jimbo

 

[DragonPoet]

So would you need a actually copy of Windows XP for a Virtual OS?

 

[hjonesMCT]

Hey there,

Yes, you got it. You will always need a copy of whatever OS you are using in a VM. Remember, VMs are just like any other regular computer.

That said, if you are running Win7 Ultimate or Enterprise, you can download Windows XP Mode, a free XP VM from Microsoft that runs under Virtual PC.

Sent from my Evo 4G. Please to excuse my engrish typing

 

[DragonPoet]

Cool, so do I need a separate partition for the VM then?

 

[kado897]

No. For either VirtualBox or VMware Player (both free) it just creates files on your hard disk for the guest machine. These files will be several Gb of course to start and may grow with time as you add things to your Guest OS.

I recently posted a comparison between the two which you can find here. http://www.sevenforums.com/virtualization/161128-virtualbox-vmware-player.html