Virtualisation – Definition and meaning
What is Virtualisation? Virtualisation explained: definition, functionality, specific application examples and recommendations for IT infrastructures. Advantages and challenges compactly
Definition and basics
Virtualisation describes a process by which physical IT components such as servers, storage or networks are converted into abstracted, virtual instances. At the centre is the software layer of the hypervisor, which makes it possible to divide up the hardware of a server in such a way that several independent operating systems - so-called virtual machines (VMs) - can run in parallel on the same physical infrastructure. This decoupling of physical and logical resources significantly increases the utilisation of existing devices, while at the same time increasing flexibility in the management and operation of the IT environment
Types and functionality
Virtualisation is implemented in various forms, each tailored to specific requirements and purposes
- Server virtualisation: with this method, several virtual servers including individual operating systems run on a single piece of physical hardware. Typical solutions in this area come from providers such as VMware (ESXi), Microsoft (Hyper-V) and KVM
- Desktop virtualisation: Here, complete workstation environments are hosted centrally in the data centre and made available to users via remote access. Platforms such as Citrix Virtual Apps and Desktops or VMware Horizon are frequently used for this
- Storage virtualisation: Different physical storage resources are combined in a shared storage pool and dynamically allocated as required
- Network virtualisation: Network functions are provided under software control, for example through Software Defined Networking (SDN) or VLANs, in order to create flexible, scalable structures
At the centre is the hypervisor as an intermediary between hardware and operating systems. For example, if you use a server with a hypervisor, you can operate several independent virtual machines on it: One system hosts four virtual servers, one of which runs on Linux and the others on different versions of Windows - each operating system without direct access to the others
Areas of application in practice
Companies from different sectors and of different sizes use virtualisation specifically to increase the efficiency and agility of their IT infrastructure. Typical practical examples can be observed in the following scenarios
- Test and development environments: Developers can quickly set up new virtual machines to test software under a wide range of conditions - no additional physical hardware is required
- Consolidation of servers: Various services that used to run on separate, often underutilised servers are combined on more powerful systems. This significantly reduces space requirements, energy consumption and maintenance costs
- Disaster recovery and backup: Virtual machines can be easily backed up, duplicated or restored on other hardware. In the event of a failure, critical services can be kept running on an alternative infrastructure within a short space of time
- Cloud environments: The provision of private or public cloud services is often based on virtualisation - especially when flexible resource pools and rapid scalability are required
Advantages of virtualisation
The strategic use of virtualisation brings numerous operational advantages and technical simplifications
- Better utilisation: multiple virtual machines run efficiently on a single hardware platform, making optimal use of resources
- Flexibility and scalability: New servers or applications are often set up as VMs within minutes or moved to other locations
- Cost savings: Less physical hardware in operation means a reduction in energy consumption, investment and maintenance costs
- Simple administration: Many administrative tasks such as updates or data backups are centralised and can be largely automated
- Business continuity: In the event of hardware faults or planned maintenance measures, the migration or recovery of VMs enables operations to be resumed quickly
Possible disadvantages and challenges
Despite its many strengths, virtualisation also brings challenges and risks
- Complexity: reliable operation of virtualised environments requires specialist expertise and targeted training for administrators
- Licence costs: High-performance hypervisors and comprehensive management tools often incur not inconsiderable licence fees
- Security aspects: If a virtualised environment is configured incorrectly, security vulnerabilities can arise - especially if different virtual systems are running on the same hardware
Virtualisation is always recommended when several independent server services are operated or when fast and flexible provisioning is required - for example in lab and test systems, when resource requirements fluctuate greatly or as part of high-availability and emergency strategies. Virtualisation has established itself as the standard in these scenarios and enables sustainable and future-proof IT operations
Frequently asked questions
Virtualisation refers to the process of transforming physical IT resources such as servers, storage and networks into virtual instances. This is done using a hypervisor that enables multiple independent virtual machines on a single piece of hardware. This technology increases resource utilisation and offers companies more flexibility and efficiency in IT management.
Virtualisation works by installing a hypervisor that acts as an intermediary between the physical hardware and the virtual machines. The hypervisor divides up the hardware resources and makes it possible to run several operating systems simultaneously. This allows companies to run different applications and services efficiently and independently of each other on the same infrastructure.
Virtualisation is used in various areas, including server consolidation, test and development environments and disaster recovery. Companies use this technology to manage resources efficiently, reduce costs and increase reliability. Virtualisation is also a key technology for cloud services that offer flexible and scalable IT resources.
The advantages of virtualisation are manifold. These include improved resource utilisation, as several virtual machines can run on one physical hardware, as well as increased flexibility in the provision of IT services. Companies benefit from cost savings thanks to reduced hardware requirements and simplified maintenance processes, which increases overall efficiency.
Server virtualisation refers to the hosting of multiple virtual servers on one physical hardware, while desktop virtualisation provides complete work environments centrally in the data centre. Server virtualisation focuses on the efficiency and utilisation of server resources, while desktop virtualisation enables users to access their work environments from different devices.
There are several types of virtualisation, including server virtualisation, desktop virtualisation, storage virtualisation and network virtualisation. Each type has specific applications: Server virtualisation optimises server resources, desktop virtualisation enables remote access to workstations, storage virtualisation pools storage resources, and network virtualisation provides flexible network structures.
Virtualisation can have both a positive and negative impact on IT security. On the one hand, it enables isolated environments that minimise the risk of security incidents. On the other hand, vulnerabilities in the hypervisor can potentially jeopardise all virtual machines. It is therefore important to implement security measures in a targeted manner in order to make the most of the benefits of virtualisation and minimise risks.