Although server virtualization is an equal opportunity platform for all operating systems, it is and will continue to be a boon to enterprise Linux adoption, says VMware Inc.'s director of data center products Patrick Lin.
In this interview with SearchOpenSource.com's site editor Jan Stafford, Lin talks about VMware's historical connection to Linux, how virtualization makes it easy to switch to Linux and the traits that make Linux a plus for application productivity. He also discusses the role virtual appliances will play in reducing operating system sprawl in virtual environments.
SearchOpenSource.com: VMware takes a stance of being operating-system agnostic, but do you see a particular synergy between virtualization and Linux?
Patrick Lin: They're very highly complementary. The first product we put out at VMware -- the first version of Workstation -- was actually based on Linux.
In a lot of cases, virtualization can allow you to migrate things into a different operating system environment without a lot of risk. Legacy re-hosting is one example. Another example is if a company has been predominantly a Windows shop but wants to start experimenting with Linux. One of the safest and least impactful ways to do that is to create some Linux VMs [virtual machines] on top of the existing virtualized infrastructure.
Virtualization ensures that that instance of Linux is completely isolated from all perspectives, including performance. VMware virtualization supports unmodified guest operating systems, which means that companies can choose whatever Linux type they want and run it. That really eases Linux's entry into environments that are dominated by Windows.
SearchOpenSource.com: Are there any differences between deploying virtual machines on Linux as opposed to other operating systems?
Lin: No, you treat it the same way. But one of the things that makes virtualization well suited for Linux is the fact that Linux does come in so many flavors and is upgraded pretty rapidly. Virtualization allows you to choose the operating system that best suits your application.
When deploying their infrastructure, customers want to try and keep it relatively standardized to make things simpler; that is a little bit at odds with the desire to make sure that they've got the operating system that best matches their application requirements.
Virtualization allows companies to standardize at that virtual hardware level but to continue to have a choice on the actual version and vendor of the operating system without having to worry about some differences that introduces.
SearchOpenSource.com: Wouldn't having many different versions of Linux in an environment lead to OS sprawl, an issue that people have raised as a potential problem resulting from virtualization? And, with the frequent updates that can increase Linux distribution capabilities, isn't there an additional management burden that comes with running various distros under one roof?
Lin: It does play in that direction, but that's also what the virtual appliance concept is designed to help with. Virtual appliances package the pre-configured application and operating system in a virtual machine.
With virtual appliances, you don't have to worry about all those different layers of software and their configurations and keeping them up to date with the patches and so on. It's turnkey. Deployment is as easy as deploying a virtual machine. The pre-configured appliance lets you focus on what you care about, which is the application, and it lets the appliance take care of making the rest of the stack work.
SearchOpenSource.com: Linux has always played a key role in IT appliances, hasn't it? Did you see many Linux-based appliances among the applicants in VMware's recent virtual appliance contest?
Lin: Yes to both questions.
Look at hardware appliances today and you'll see that most of them are based on Linux and were based on Linux to begin with. Linux is so easily redistributable and can be streamlined to meet the needs of the application. Those things all hold true in the virtual world as well.
One of the winners in our appliance contest is the Sieve Firewall, a firewall virtual appliance that is running on Linux but has been designed to come out of the box with a Windows interface. It runs as an ISO image inside of the VM.
So, what does that mean? One, it's taking advantage of the special properties of virtualization in that it's an ISO; it can't be written to as a CD-ROM. And two, there's Linux in there, but nobody has to know about. If somebody is more comfortable with the Windows interface, it's there. It is easy for Windows admins to set up. They don't have to learn Linux.
Appliances have and virtualization will make Linux even more pervasive than it already is.