Virtualisation is the foundation of cloud computing but what are some of the key benefits it can bring to your organisation?
Many IT organisations deploy servers that are only running at a fraction of their capacity, often because they are dedicating their physical server to a specific application. This is usually an inefficient mechanism because there is an excess capacity that is not being consumed, which leads to higher operating costs and IT costs.
The concept of allocating virtual resources to operating systems and applications, rather than dedicating specific server hardware and software to those computing assets, has become a fundamental principle of datacentre design and operations over the past couple of decades and server virtualisation has been a real “game-changer” for the datacentre and those who administer and manage it.
What is virtualisation?
Virtualisation is technology that lets you create useful IT services using resources that are traditionally bound to hardware. It allows you to use a physical machine’s full capacity by distributing its capabilities among many users or environments.
Most commonly, virtualisation refers to running multiple operating systems on a computer system simultaneously. To the applications running on top of the virtualised machine, it can appear as if they are on their own dedicated machine, where the operating system, libraries, and other programs are unique to the guest virtualised system and unconnected to the host operating system which sits below it.
Virtualisation can increase IT agility, flexibility and scalability while creating significant cost savings. Greater workload mobility, increased performance and availability of resources, automated operations – they’re all benefits of virtualisation that make IT simpler to manage and less costly to own and operate.
Types of server virtualisation
There are three different kinds of server virtualisation:
Virtual machine model (or “full virtualisation”)
Based on the host/guest paradigm, use a special kind of software called a hypervisor. Administrators can create guests with different operating systems.
Paravirtual machine (PVM)
Similar to full virtualisation, also based on a host/guest paradigm. Can also run multiple OSes.
Not based on the host/guest paradigm. Guests must use the same OS as the administrator/host, and partitions are completely separated from one another (so problems in one cannot affect any others).
What is a hypervisor?
A hypervisor is a program for creating and running virtual machines. Hypervisors have traditionally been split into two classes: type one, or “bare metal” hypervisors that run guest virtual machines directly on a system’s hardware, essentially behaving as an operating system. Type two, or “hosted” hypervisors behave more like traditional applications that can be started and stopped like a normal programme.
In modern systems, this split is less prevalent, particularly with systems like KVM. KVM, short for kernel-based virtual machine, is a part of the Linux kernel that can run virtual machines directly, although you can still use a system running KVM virtual machines as a normal computer itself.
10 key benefits of server virtualisation
The advantages of server virtualisation are compelling; here are some of the benefits you can expect by virtualising server infrastructure:
1. Reduced hardware costs
Datacentres contain numerous physical servers that are dedicated to handling the workload from a network. This hardware is expensive, so if you don’t need every server in the facility, that means you’re wasting money on hardware resources, power, cooling, and maintenance.
When you implement a virtualised server/cloud computing approach, hardware utilisation is increased because one physical server can now hold multiple virtual machines. Applications no longer need their own server because each virtual machine on the physical server now runs them.
Virtualisation, therefore, allows you to reduce the number of physical servers you need to run your business.
2. Faster deployment
Server virtualisation enables system provisioning and deployment within minutes, allowing you to clone an existing virtual machine without the hours and costs normally spent procuring and installing a new physical server.
In the past, installing a physical server is a long, arduous, and expensive process. First, you have to order the server, followed by waiting for the hardware to arrive. Then you’ll have to wait for the operating system and applications to install before finally being able to use it—not to mention that you’ll also need to purchase and house racks and cables for the growing number of physical servers.
Virtualisation is most certainly necessary for most businesses to keep up with the explosion of data resources needed to keep pace with competitors.
3. Save space
We have touched on it above, however, because each physical server takes up a certain amount of space, there are only so many you can own. That number is directly dependent on your datacentre’s capacity.
This isn’t as much of an issue with virtual machines, however. Although they still need a physical server to be on, virtual environments only take up virtual space. This means you can multiply the number of available servers you have without needing to create extra space.
Regardless of the size of your business or the space you have on-premise, it’s always a good idea to save space and free up resources for other areas of the business.
4. Reduced energy costs
Physical servers produce a lot of heat, and if they get too hot, they don’t work effectively. To prevent overheating, servers need to be cooled. Since virtual servers reduce how many physical servers you need, you won’t have to spend as much on cooling services. A lower number of servers also means there are fewer machines that need power.
All of this adds up to significant cost savings from an energy perspective alone. Whilst the major cost-savings of server virtualisation are realised via reduced hardware purchases, the energy cost savings should not be overlooked when assessing the benefits of server virtualisation.
5. Simplified disaster recovery
When a disaster affects a physical server, someone is responsible for replacing or fixing it—this could take hours or even days. Perhaps the greatest benefit of server virtualisation is the capability to move a virtual machine from one server to another quickly and safely.
Backing up critical data is done quickly and effectively because your company can effortlessly create a replication site.
Most enterprise virtualisation platforms contain software that helps automate the failover during a disaster. The software also allows you to test a disaster recovery failover—think of it as your datacentre’s own fire escape plan.
If a datacentre disaster occurs, your infrastructure is already set up to take appropriate measures for a swift and safe recovery. Try achieving that with arrays of physical servers—now that’s a real disaster.
6. Increased efficiency
With fewer servers, your IT teams will be able to spend less time maintaining the physical hardware and IT infrastructure. You’ll be able to install, update, and maintain the environment across all the VMs in the virtual environment on the server instead of going through the laborious and tedious process of applying the updates server-by-server. Less time dedicated to maintaining the environment increases your team’s efficiency and productivity.
Faster server provisioning will also yield overall improvements in IT productivity. New servers can be spun up and deployed quickly without requiring a lot of time. When a server is no longer needed, it can easily be decommissioned and taken down.
7. No more server sprawl
Server sprawl is a common occurrence in datacentres, as new servers are added to handle new applications while older server gear either continues to handle some chores or sits unused.
Before server virtualisation existed, administrators would have to over-allocate server resources to meet demand. Since server virtualisation creates multiple virtual servers within a single server, admins are no longer forced to over-allocate resources.
With server consolidation, fewer pieces of hardware are required, so IT can consolidate physical resources, which can yield considerable savings on maintenance contracts, power and cooling, and overall footprint.
8. Flexibility and scalability
A virtualised infrastructure offers far more flexibility and easier scaling than a traditional environment. Virtual servers can be moved or cloned from one piece of hardware to another, making hardware upgrades and performance tuning a nearly effortless process. Similarly, these capabilities can be tapped to transition to a cloud service or to maintain a hybrid infrastructure that spans on-premises and cloud resources.
9. Increased uptime
Features like vMotion, storage vMotion (svMotion), DRS, and VMware high availability (VMHA) all result in virtualised servers being up and running so much more than those same servers that were running directly on physical hardware.
When you are able to cut down on the number of physical servers you’re using, it will lead to a reduction in the amount of power being consumed. This has two green benefits:
- It reduces expenses for the business, and that money can be reinvested elsewhere
- It reduces the carbon footprint of the datacentre
Virtualisation is a powerful tool that helps relieve administrative overhead while increasing cost savings, scalability, and efficiency. Despite being created decades ago, virtualisation continues to be a catalyst for companies’ IT strategies.
The importance of virtualisation is being exponentially accelerated as companies look at their IT modernisation journey. Expect more and more companies to turn to server virtualisation over the next 2-3 years.