Virtualization – The Long and Short of It
New, up and coming terms like virtualization, data centre and cloud computing are often out of reach for most of us out there but after doing some research, it’s clear to me now that, to understand the concepts, you need to ask the right questions. The obvious one being what is virtualization?
Basically it’s a platform which enables a single user access multiple devices, something like a single computer controlling multiple machines. In other words, we have a system / server where the virtualization platform is installed and on that platform several operating systems are installed. Hence the user can access any of the operating systems at any given time or even simultaneously. To an outsider it looks like 3 different systems are at work while in reality, its only one server.
Virtualization solves a problem of buying and managing a lot of servers at any given time. It saves a lot of trouble in case of a server failure and makes the entire system compact.
To understand the concept much more clearly, consider its 3 subsections, host operating system, the hypervisor, and the guest operating system.
Host OS: it is the original OS with which the virtual machines share all information. The virtualisation platform is installed here.
Hypervisor: It is a program which allows multiple OS to share a single host. This enables the OS to have the host OS’s memory. The hypervisor handles memory allocation and resources of the virtual machines and makes sure that they don’t interfere with each other.
Guest OS: simply put, an OS other than the host OS which is sometimes installed is called a guest OS. It’s usually installed inside the virtual system. For e.g. the OS windows, Linux and MAC are the guest OS on the virtualisation platform of the Host OS.
It is crucial for the virtualisation administrators to monitor and manage the platform resources like I/O traffic diligently. They should make sure that they are optimising the host resources and prevent performance degradation.
Now, there are the different types of virtualization and companies provide specific domain solutions for them. There are essentially three types:
This is the most common type implemented in the IT industries as well as in the data centres. The host Server is virtualized and hence allowing the server to be able to run different OS simultaneously on the same hardware.
It has several benefits namely, less no of servers, easier and faster addition of capacity as per needs & less power consumption.
This means that the end users(us) data are all stored in a VM(virtual machine) in the hosted environment which can be of the IT ‘s in house or of the data centers. They can be managed in one place for all the users of the company. This process has few takers as it requires a lot of work and takes a lot more planning to execute it.
Consider this, when a company is growing, it will need more space, even for the servers it’s using, and before you know it , it’s going to increase tenfold. Hence the company needs proper plans for disaster control that’s where this comes to picture. This ensures that multiple storage devices appear as one common media. Storage virtualization takes care of that.
Virtualisation is adopted by honchos like citric and Microsoft but there are other companies like HP, IBM, oracle etc have entered the market. The conclusion is that the more completion in the industry the more affordable it becomes for the end user.