Virtualisation is the process of converting a physical server into a single file that is then run by a server called a Hypervisor. This process is often called physical to virtual conversion or P2V. Traditional servers typically consist of 1 physical server which then has an operating system installed on it. This scenario has a number of drawbacks. Firstly if the server breaks and a new server has to be purchased, the server will have to be reinstalled. Even with a full backup, this can sometimes take a week or more to get everything back working exactly as it was. The cost to the business in this case is immense. Virtualisation improves upon this by reducing the time from a replacement server arriving onsite to being fully operational to approximately 3-4 hours. The second drawback of non-virtualised servers is scalability. Often by the time a Windows Server is 2-3 years old, businesses needs have changed such that server is having to store more files and do much more work. Eventually it will need to be upgraded. If the server can support these upgrades, this is ok. But eventually a fundamental limit will be reached on what can be upgraded. As this stage the entire server is usually replaced, including all the software. This may take a week or so to complete fully. Virtualisation allows continuous and limitless upgrades to the physical hardware since in the worst case scenario, the entire physical server can be replaced in a matter of hours.

SR Networks specialises in two key areas of Server virtualisation. Firstly we can take any Windows 2003 or later server and turn it into a Virtual Machine. This physical to virtual (P2V) conversion results in a VHD file which can then be easily placed on a Windows HyperV server. We can also create VMWARE files if required. The second key area we can help is in the provision of HyperV Clusters. HyperV Clusters are a collection of 2 or more Windows Servers running together as a cluster, on top of which HyperV runs. The servers can be, and ideally should be, on different sites or at least different buildings. If one server fails, the other server will take the load with no interruption to the users.

Server virtualisation

Key virtualisation services offered by SR Networks
  • Physical to virtual conversion (P2V) of existing physical servers
  • Installation and/or setup of Windows Hypervisor Server (HyperV)
  • Load-balancing of virtual machines to reduce hardware bottlenecks
  • HyperV clustering over multiple physical servers, sites and links
  • Virtual Server Backup using proprietary scripts
  • Documentation and training for in-house IT staff
  • Integration into existing Disaster Recovery Planning or creation of a new plan
Business benefits of Server virtualisation
  • Consolidation of physical servers – reducing space, power and cooling requirements
  • Reduction of capital and IT management costs by having less hardware to support
  • Increased availability of resources through reduction in Server downtime
  • Deliver resources and applications in an efficient and scalable way
  • Faster disaster recovery response time
  • Extending the lifespan of existing servers and applications

Desktop virtualisation or PC virtualisation can take 2 forms, the difference being on where the virtual computer’s VHD file is located. In the first type the VHD file is located on a Windows Server running a Hypervisor such as HyperV. It is sometimes called Virtual Desktop Interface (VDI). The majority of the benefits above stem from this type as because the VHD files are on the server this simplifies backup, resource & space allocation and allows any Physical Computer to access any Virtual Computer. Many companies currently use Terminal Server (now called Remote Desktop Services) to provide a remote desktop for their users. But this can be very expensive in terms of licenses. The one major benefit of this type of Computer virtualisation is that you can virtualise your old PCs and then run these from the server. This allows you to extend the life of the PC and also reduce downtime if the physical PC has a fault.

The second type of Desktop virtualisation is where the virtual computers VHD file is located on a particular PC. This has been around for a while but most people know this as Windows XP Mode, available for free as part of Windows 7 Professional. This is much cheaper than using a Server Hypervisor, but limits the Virtual Desktop to only being used from one PC. However, it is ideal for situations where a company has one very old PC running an application that cannot be easily transferred to a newer PC. In this case we would virtualize the entire computer and then run it as a virtual desktop on top of a more modern PC and operating system.

Desktop Virtualisation (Virtual Desktop Infrastructure, VDI)

Business benefits of Desktop virtualisation
  • Consolidation of physical servers – reducing space, power and cooling requirements
  • Reduction of capital and IT management costs by having less hardware to support
  • Increased availability of resources through reduction in Server downtime
  • Deliver resources and applications in an efficient and scalable way
  • Faster disaster recovery response time
  • Extending the lifespan of existing servers and applications