Going Virtual – How to Virtualize your Linux/PC Environment
There is a term/concept you might hear related to PC’s and operating system. The term you might hear is “bare metal”. Bare metal as in installing an operating system on ‘bare metal”. What does this mean?
This term, bare metal, is only possible because of another term – virtualization. You might hear the term “guest operating system”. A guest operating system runs on a platform that supports virtualization.
So what is virtualization? In simple terms it means that you have some software that is capable of emulating the hardware of a PC to the point that you can install on operating system on it and have it run as if it was on bare metal.
So, if you put this all together, bare metal is the real hardware. Virtualization is the capability to emulate PC hardware in software to the point that you can install an operating system and have it work as if it was bare metal. The installed operating system in the virtualized environment becomes the guest operating system. The guest operating system run’s in a virtual machine in the virtualized environment
The really cool thing, is that if you have a nice big server with lots of CPU, memory, disk, and other hardware resources plus reliable software that can create the virtualized environment you can run a lot of guest operating systems on a single server.
Here is a more concise definition of virtualization:
Virtualization is an abstraction layer that decouples the physical hardware from the operation system to deliver greater IT resource utilization & flexibility.
You too can become virtualized
That CxO’s (CTO’s, CIO’s) of Fortune 500 companies have embraced virtualization is a testament to the success of this technology – and to the fact that benefits can be measured and demonstrated in financial terms and against SLAs (Service Level Agreements)
Companies have saved ten of millions of dollars by consolidating low utilization individual bare metal servers (real hardware) into guests in a virtualized environment. A mid to large corporate environment may have 2,000+ servers supporting the business. The potential for saving by consolidating this environment, where feasible, and reducing the server count is huge.
What works for the big corporations can work for you in your home as well. And best of all, the technology that can accomplish vitualization for you in your home is free.
The reason for this posting is the previous posting made on Clonezilla to do disaster recovery backups of Linux systems.
Really, we want to make sure the readers of this site know another way to run Linux that pretty much mitigates the challenge of doing disaster recovery backups of Linux systems. If you read the PDF article that we included with the posting on Clonezilla you can see how complex Linux backups can be.
This is not to say that what we are about to suggest will eliminate the need for products like Clonezilla but it certainly solves the problem of backing up Linux systems or any operating system for that matter.
Microsoft Virtual PC 2007
Lets ask this question – why do you need to install Linux on bare metal? Why should one allocate an entire PC for the purposes of running an operating system?
Well, before virtualization the questions above would not make any sense. But now, with mature virtualization technology – and best of all free virtualization technology – why would you ever want to run an operating system on bare metal? Is that a good use of your PC resources? In addition, you gain new capability that you had never before considered.
So, lets cut to the chase. One of the free virtualization products out there is Microsoft virtual PC 2007. It’s free. Yes, totally free, it has a small footprint, and is easy to use. It is sized for home use.
What works in a corporate environment can work for you at home
Ok, so we posted an article in the recent past and suggested you to use Clonezilla for disaster recovery. As an alternative, how about installing Linux on Virtual PC 2007 along with your existing operating systems. Wouldn’t that be a better use of hardware?
Here is even a better justification. Suppose you don’t have a bunch of (bare metal) PC’s on which to install a variety of operating systems? Virtualiztion can solve your problem.
Seeing is believing. Or, “Show me”
Enlarge the image below and take a good look at this.
Here is what is going on. This is a Windows Vista machine running Virtual PC 2007 with a two guest operating systems running. One guest is the SuSe Linux 11.1 and the beta of the next release of Windows – Windows 7 Beta.
Both of these operating systems are running in individual windows in Vista. You also have the option to run any of them full screen. In this latter mode, its hard to tell that these are guest machines in a vitualized environment.
If you look at the Virtual PC console you can see the virtualized hardware devices. Want to add more memory to your Linux machine? Then just do it – use Virtual PC 2007 and type the amount of memory you want your Linux machine to see and reboot. Want to add another hard drive to Linux? Then just do it – use Virtual PC 2007 to allocate a new virtual disk and reboot. Use Linux to format it, partition it, and add file systems as if it was real.
We won’t go on, you get the idea. Of course you realize that adding more memory and more disk as seen by the guest operating systems is limited by what you really have on the machine hosting Virtual PC 2007. And of course you take a performance hit. But with a fast enough PC you may not even notice as compared with Linux running on bare metal on a lesser machine.
The specifics of what you see here is a HP desktop with 4GB of Ram, dual core 2.4 GHz CPU , and a little over 1 TB of disk space. As of February 2009, a 1 TB disk drive can be had for $89. 1 GB of Ram is $37. So there is not a huge investment in this setup.
Finally, the issue of disaster recovry in a virtualized environment
So, the real motivation for this posting is to talk about disaster recovery backups. How do you backup a virtual machine? Easy! You simply copy a folder of 2 files on the host operating system. That’s it. You don’t need Clonezilla, you don’t need any fancy Linux backup program. Simply copy the folder containing the the virtual hard drive and the virtual machine configuration file and you are done. These image below shows all the files related to the two guest operating systems shown running in the screeen shot above.
In 2009, virtualization is mature technology that is used in Fortune 500 companies. It can work in your home as well as a way to more efficiently use your existing computer resources and perhaps provide you with capabilities that you did not have in the past. For example, you might not have enough individual PC’s to run multiple operating systems. But you may have a PC that has enough resources to run virtualization software that can run multiple guest operating systems.
Microsoft Virtual PC 2007 is only one of many solutions on the market. We think that Virtual PC 2007 is a good choice for the home user. It does not require a lot of resources and it is very easy to use. Best of all, it’s free.
In a sense, the complex challenge of disaster recovery of operating systems is not eliminated – it’s mitigated. Disaster recovery, a complex challenge on bare metal is reduced to a simple folder copy on the host in a virtualized environment.
So, give Microsoft Virtual PC 2007 a try – what do you have to lose?
The defacto corporate solution – http://vmware.com/
For tough guys – http://wiki.openvz.org/Main_Page
Another solution – VirtualBox with numerious pre-built guest operating systems