What is virtualisation and is it really going to revolutionise IT management?
It seems like everything is being virtualised these days. Even a cursory glance at their back-offices reveals that businesses are now operating in an increasingly virtual environment. Storage, servers, applications - nothing has to reside in a box in a specific location for users to access them any more. According to statistics, the virtualisation market skyrocketed to roughly $US1.2 billion last year and by 2007 it will surge to $US2.2 billion. At its simplest level, it either describes several things working together as one entity, or one entity working as several things. It is an arbitrary representation of a physical resource. A common analogy is that of a bunch of employees from different departments & offices all cooperating as one project team.
The virtualisation of servers, for instance, is steadily making the IT world sit up and take notice. Enabling multiple virtual operating systems to run on a single physical machine, yet remain logically distinct with consistent hardware profiles, server virtualisation can often replace the costly practice of manual server consolidation by combining many physical servers into one logical server. With multiple operating systems and their applications, all able to run on a single server, IT departments can enjoy improved management, flexibility and compatibility as well as vastly increased hardware utilisation.
"There are certainly savings on operational costs, because there are a lot of costs associated with running a server - data centre space, data centre power and data centre cooling for instance, But there are also operational expenses associated with labour - provisioning servers and changing servers, bringing new applications on line, patching them and so on and so forth - so there is a pretty dramatic reduction in labour costs as well." And then of course there are actual hardware savings, because very often instead of running ten servers that are all lightly loaded you can use one server that is more heavily loaded because all the applications can now run on one box.
Costs and security
Elsewhere in the virtualisation universe there is operating system virtualisation (where a single computer can accommodate multiple platforms and facilitate their operation simultaneously); application virtualisation (where end-user software is packaged, stored and distributed in an on-demand fashion across a network); and data virtualisation (allowing users access to various sources of disparate data without knowing where the data actually resides).
Because physical devices and applications are represented in a virtual environment, administrators can manipulate them with more flexibility and reduced negative effects than in the physical environment. Heterogeneous hardware can be used together and scalability can be achieved by simply plugging extra capacity into the virtual resource pool. The addition or removal of hardware can be easily managed with virtualisation tools. Operating costs can also be lowered while performance, connectivity and capacity can be improved, and therefore maintenance costs lowered. Continuity is also assured as resources can be spread and mirrored and any one element can be taken offline or replaced without impacting other elements.
And despite consumer concerns over the implications that virtualisation may have on security, the technology can also prove beneficial in this area.
Network virtualisation
Elsewhere, network virtualisation is having a similar impact, as multiple networks are combined into a single network or single networks are separated logically into multiple parts. With a virtualised network environment, the underlying architecture is invisible to users and services are no longer associated with a specific device or connection. Instead, they are accessed via a common applications interface and the network will figure out how to deliver a service to the user, whether access is via desktop, PDA or mobile phone.
While storage, server and network virtualisation are well-established technologies, PC virtualisation is perhaps less well-known. The concept behind this field of virtualisation is that a single physical computer simultaneously runs multiple virtual PCs, each with its own operating system. Tech giants such as Intel, for instance, has developed a technology based on dual- or multi-core CPUs that make it easier to run Windows, Linux, Unix or Solaris side by side but as entirely separate entities that are allocated individual portions of CPU power, memory and hard disk space.
Network managers that need to evaluate the performance of applications under different platforms will certainly see the benefit of this approach, whilst the development community will also recognise the value to putting new hardware and software to the test. Productivity could certainly benefit, as users can run different applications without having to switch machines or location. And security will also benefit, as running antivirus tools or firewalls to protect web browsing on one operating system will effectively isolate dangerous traffic from attacking mission-critical applications running in another.
Virtualised environment
Nevertheless, some trepidation remains, and for some the concerns stretch beyond security. The short-term costs of an ambitious virtualisation project can be expensive, with the need for new infrastructure and configuration of current hardware. And such an investment is difficult to justify to a board that remains somewhat confused by the technology.
Indeed, while wariness of an expensive IT project is entirely understandable, the virtualisation revolution will inevitably continue unabated. As costs for the technology begin to drop, consumer understanding of the technology grows, and more hardware manufacturers such as Intel include built-in virtualisation functionality in their products, it will become increasingly difficult to justify not deploying virtualisation in an IT system.
"Virtualisation has been occurring for decades now, it is just cascading now to other parts of the infrastructure as other technologies evolve and mature, where we see it going next will be towards this idea of a heterogeneous mutli-system virtualisation, and away from the component-based view, to look at the infrastructure holistically." The evolution towards a more virtualised enterprise is inevitable. "It is already on its way to ubiquity," he concludes. "Over the next few years we are going to see more and more widespread adoption. Leading-edge customers are already moving towards this notion of what we call a `virtualised enterprise`, where all your applications run in a virtual environment for all the benefits that we have discussed, and all your desktops move to a virtualised environment running on servers so that it is more secure and centrally managed. So it will start to permeate every aspect of IT operations
John Paul
http://www.swansol.com/blog