In computing, a single, physical server can be segmented into multiple isolated and virtual servers using some software. Each virtual server can run its own operating system (OS) independently.
Among other reasons, This is done to tighten control over all server users. Server virtualization allows users to only have access to resources that are specific to their instance.
Users on a virtualized server cannot identify the total number of processors of the operating systems, virtualized servers, and other physical servers.
They can also only use the CPU cycles and memory associated with their instance. This prevents them from affecting other users of the server.
How server virtualization works
Servers are computers that handle requests from other computers in a network. One server is usually dedicated to a single task or application. This can lead to unmanageable numbers of servers in a network, depending on how many applications and tasks are being performed.
Servers consume space and power to operate. Modern servers are more resource-intensive than necessary to run the specific tasks and applications they need. Inefficient use of computing power can lead to servers using more energy than necessary. Servers must be managed so that they can consume less energy and still have the ability to perform computing tasks.
Server virtualization reduces server inefficiencies. It uses software to split a single physical server into many fully isolated virtual servers. Each virtual server can run its own operating system and complete tasks using the resources of the parent server.
Also read: Top 10 Server Backup Software
The benefits of server virtualization
Organizations can reap the benefits of virtualization. Server virtualization benefits are not only beneficial for streamlining network requirements but also include:
- Saving Space: If only one task or an application is running on a server, it will quickly take over your data center. By hosting multiple virtual servers on fewer physical servers, you can potentially save a lot of physical space.
- Lowering Hardware Prices: It can be expensive to build physical servers. Virtual servers can be deployed for a fraction of the cost.
- Improving Resource Efficiency: Many servers are much more powerful than they need to meet the needs of their customers. Organizations technically have to pay for any unused resources. Virtualization ensures that all resources are efficiently utilized.
- Less Energy Costs: Virtualization makes it possible to use server resources more efficiently than building unnecessary infrastructure. you have fewer servers using energy.
- Reducing IT Demand: Maintaining large networks of servers can prove to be a burden on an IT department. Virtualization allows IT workers to focus on business needs and frees up IT resources.
- Speeding up Setup: Between purchasing hardware and implementing it, it can take days or even weeks. It can take only minutes to set up virtual servers.
- Simplifying Recovery: Backup systems on virtual machines are fast and efficient. This allows you to quickly recover from a system crash with minimal data loss.
Drawbacks of Server Virtualization
Server virtualization is not perfect. Virtualization has its downsides.
- Increasing upfront costs: New hardware and licensing fees can lead to higher upfront costs.
- A slight decrease in performance: Users might notice a slightly lower performance when resources are shared, particularly with hypervisor-based virtualization. It might take tasks a bit longer to complete. This is changing with the advancements in server virtualization technologies.
- Server Spraw: Administers can accidentally overbuild their network because VMs are so easy to create. This is called VM sprawl. If 10 servers are not sufficient, you can build 20 VMs.
Five Types of Server Virtualization
Virtualization is a popular solution for organizations across all industries. It solves many big problems such as managing server resources, reducing infrastructure costs, and easing IT demand. Network administrators can rely on a variety of server virtualization options. Examples of server virtualization include:
- Full virtualization.
- Hardware-assisted virtualization.
- OS-level virtualization.
- Hypervisor virtualization.
1. Full Virtualization
Full virtualization uses software called a Hypervisor which divides the server’s resources among completely separate virtual servers that are isolated. The hypervisor controls how resources are distributed between virtual servers. Because the virtual machines run on separate operating systems, each one can be configured to suit its needs.
Para-virtualization can be thought of as a subset of full virtualization. A hypervisor can access virtual machines through interfaces that are very similar to the underlying hardware. Para-virtualization is a process that modifies a guest operating system to allow other guest OSes on the server to communicate and share resources. All the VMs work together so there is less demand on the hypervisor. This means that more resources for server virtualization are available for virtual servers.
3. Hardware-Assisted Virtualization
Hardware-assisted virtualization already includes the ability to divide resources required for multiple VMs. Virtual machines can communicate directly with the main server instead of through the hypervisor. Although it is a way to cut down on the middleman, a hypervisor will still be required. The hypervisor consumes a significant portion of the server’s resources because the connection between virtual machines and physical servers is much more direct. It appears that the virtual machines are running on the server.
4. OS-Level Virtualization
A hypervisor is required for full virtualization, paravirtualization, and hardware-assisted Virtualization. It provides a platform where virtual server operating systems can run. With OS-level virtualization, however, The host server’s OS-level virtualization allows for multiple virtual machines, called containers. The VMs work in the same manner in OS-level virtualization and hypervisor virtualization. However, the host operating system’s computing overhead is much greater than that of a hypervisor-based system. OS-level virtualization is simpler and more cost-effective for new users.
5. Hypervisor-Based Virtualization
Hypervisor-based virtualization allows software (the hypervisor), to emulate the hardware of the main servers. It acts as a physical machine that operating systems can run on. The hypervisor distributes the resources of the main server to the guest virtual machines.
Hypervisor-based virtualization can be used for full virtualization or para-virtualization. Hypervisor-based and hardware-based, hardware-assisted hybrid virtualization is one type of hybrid virtualization.
Server Virtualization: What to Consider
Server virtualization can improve the computing system of an organization in many ways. Virtualized servers allow IT to spend less time working on internal networks, reduce data center space, optimize server resources, and lower hardware and energy costs. A virtual machine can be set up much faster than a physical server.
Server virtualization can be associated with multi-tenant or shared server resources. Multi-tenant servers can be more cost-effective and powerful than single-tenant servers, but they also come with potential problems like noisy neighbors or additional security and stability issues.
A bare-metal approach to virtualization can help to reduce these risks. Bare metal virtualization allows you to be the single tenant that uses the server’s resources even though there is still an administrator managing the virtual servers. Bare metal virtualization allows you to reap the benefits of cloud computing without the risk associated with shared server configurations.