What is Virtualisation?

Virtualisation is the process of creating a virtual version of something, such as an operating system, a server, a storage device, or a network resource. It involves running multiple instances of an operating system or application on a single physical machine, allowing resources to be shared and utilized more efficiently.

virtualisation is often used in data centers, virtual data centres and cloud computing environments to improve resource utilization, reduce hardware costs, and increase flexibility and scalability. It can also improve security by isolating applications and workloads from each other, and simplify management by allowing administrators to manage multiple virtual machines from a single interface.

There are several types of virtualisation, including server virtualisation, desktop virtualisation, network virtualisation, and storage virtualisation. Each type of virtualisation has its own specific benefits and use cases, but they all share the goal of increasing efficiency and flexibility while reducing costs and complexity.

Virtualisation Servers

Virtualisation servers are physical machines that are designed to host virtual machines. These servers are equipped with specialized software, known as a hypervisor or virtual machine monitor, that allows multiple virtual machines to run on the same physical hardware.

Virtualisation servers can run a variety of operating systems, such as Windows, Linux, or Unix, and can host multiple virtual machines running different operating systems. Each virtual machine is isolated from the others and has its own virtual hardware resources, such as CPU, memory, disk space, and network interfaces.

Virtualisation servers are used in data centers and cloud computing environments to maximise resource utilisation, reduce hardware costs, and increase flexibility and scalability. They can be used to create virtualised environments for testing and development, running multiple operating systems on a single physical machine, and hosting cloud-based services and applications.

There are several popular virtualisation server products on the market, including VMware ESXi, Microsoft Hyper-V, and Citrix XenServer. These products offer a range of features and capabilities, such as live migration, high availability, and disaster recovery, to help organisations meet their virtualisation needs.

Desktop virtualisation

Desktop virtualisation, also known as virtual desktop infrastructure (VDI), is a technology that allows multiple virtual desktops to run on a single physical machine. In desktop virtualisation, the operating system, applications, and user data are separated from the physical hardware and run in a virtual machine that is hosted on a remote server.

Desktop virtualisation offers several benefits, such as improved security, centralised management, and flexible access to desktops from anywhere with an internet connection. It also allows organisations to reduce hardware costs, simplify software deployment, and provide a consistent desktop environment for users.

There are several types of desktop virtualisation, including:

1. Hosted virtual desktops: In this model, the virtual desktops are hosted on remote servers and accessed by users through a thin client or web browser.

2. Local virtual desktops: In this model, the virtual desktops run on the user's local machine using virtualisation software such as VMware Workstation or Oracle VirtualBox.

3. Remote desktop services: In this model, the desktops are hosted on a server and accessed by users through a remote desktop protocol (RDP) client.

4. Application virtualisation: In this model, only the applications are virtualized, and users access them through a web browser or remote desktop client.

Desktop virtualisation can be deployed in various ways, including on-premises infrastructure, cloud-based infrastructure, or a hybrid model that combines both. Popular desktop virtualisation products include VMware Horizon, Citrix Virtual Apps and Desktops, and Microsoft Remote Desktop Services.

Network virtualisation

Network virtualisation is a technology that allows multiple virtual networks to run on a single physical network infrastructure. In network virtualisation, the physical network resources, such as switches, routers, and servers, are abstracted and divided into multiple virtual networks, each with its own resources and policies.

Network virtualisation offers several benefits, such as improved resource utilisation, simplified network management, and increased flexibility and agility. It also allows organisations to create isolated virtual networks for different applications and workloads, which can improve security and compliance.

There are several types of network virtualisation, including:

1. Virtual LANs (VLANs): VLANs allow multiple virtual networks to run on the same physical network infrastructure, using different VLAN IDs to segregate traffic.

2. Virtual Private Networks (VPNs): VPNs create secure connections between remote networks or users, allowing them to access resources on a private network over the internet.

3. Software-defined networking (SDN): SDN is a network virtualisation technology that separates the network control plane from the data plane, allowing network administrators to manage network traffic and policies centrally.

4. Network function virtualisation (NFV): NFV virtualises network functions such as firewalls, routers, and load balancers, allowing them to run as software on standard servers.

Network virtualisation can be deployed in various ways, including on-premises infrastructure, cloud-based infrastructure, or a hybrid model that combines both. Popular network virtualisation products include VMware NSX, Cisco ACI, and Microsoft Azure Virtual Network.

Storage virtualisation

Storage virtualisation is a technology that allows multiple physical storage devices to be abstracted and presented as a single logical storage pool. In storage virtualisation, the physical storage resources, such as hard drives and solid-state drives, are combined and managed as a single resource, which can be allocated to different applications and workloads as needed.

Storage virtualisation offers several benefits, such as improved storage utilisation, simplified storage management, and increased flexibility and scalability. It also allows organisations to create virtual storage devices that are independent of the underlying physical storage hardware, which can reduce costs and simplify migration and backup processes.

There are several types of storage virtualisation, including:

1. Storage area network (SAN) virtualisation: SAN virtualisation allows multiple physical storage devices to be combined into a single virtual storage pool, which can be accessed by multiple servers.

2. Network-attached storage (NAS) virtualisation: NAS virtualisation allows multiple physical NAS devices to be combined and presented as a single virtual NAS device, which can be accessed by multiple clients.

3. Object storage virtualisation: Object storage virtualisation allows multiple physical object storage devices to be combined and managed as a single virtual storage pool, which can be accessed by multiple applications and workloads.

Storage virtualisation can be deployed in various ways, including on-premises infrastructure, cloud-based infrastructure, or a hybrid model that combines both. Popular storage virtualisation products include VMware vSAN, Microsoft Storage Spaces, and IBM Spectrum Virtualise.