What is a virtual server?
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What is a virtual server?

A virtual server is a type of software-enabled server that can be created by partitioning a physical server—often referred to as the host or bare metal server—into smaller, self-contained segments. A virtual server can replicate the functions of any type of server, while also sharing resources with other types of virtual servers.

With increased server demands, the rise of cloud computing and a greater push toward greener resource solutions, virtual servers became a staple of modern server hosting and data centers. Traditional servers require dedicated, physical hardware to handle any workload—consuming space, power and resources even while idle. Virtual servers, however, allow a single piece of hardware to host multiple servers, optimizing resources and reducing expenses. 

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How does a virtual server work?

Virtual servers are made possible by virtualization software called hypervisors that act like a layer between the physical hardware and multiple unique virtual environments. Each of these virtual environments can run its own operating system (such as Microsoft Windows, Linux or Ubuntu). The hypervisor enables server virtualization by isolating each server and managing the resources as the physical server, at times working as a load balancer and redistributing compute resources to promote efficient operation.

Benefits of virtual servers

There are many convenient use cases for virtual servers that have various benefits over traditional physical servers: 

Lower costs

Server virtualization relieves organizations of the costs that are associated with investing in a stand-alone server for every application. This not only saves money on hardware costs, but also power, cooling and data center maintenance.

Scalability

Virtual servers are an excellent solution for organizations like startups that are looking for flexible options that scale easily. Virtual servers can be used and repurposed for any number of different uses—from simple mail servers to high-performance web servers capable of handling millions of web applications

Increased capacity

Operations that make use of virtual servers are not constrained to a single server and are therefore able to take advantage of increased server capacity. Virtualization allows organizations to greatly increase available processing power since workloads can be distributed across small sections of each networked server. 

Decreased carbon footprint

Virtualization offers a greener alternative to multiple physical servers since a single physical server can run multiple virtual servers that are capable of more efficient use of resources, requiring a smaller physical footprint and less cooling related emissions. 

Instant provisioning

Whereas a dedicated bare-metal server may require lengthy setup time, depending on hardware availability and component assembly, deploying virtual servers can be done on-demand in a matter of minutes, decreasing downtime. 

Improved disaster recovery

Virtualization makes it easier to backup and replicate data across multiple centers, enabling disaster recovery (DR) specialists to assess and remedy any unforeseen critical failures more easily. Virtualization also helps safeguard business continuity and defend against cyberthreats (such as DDoS attacks) with features like live migration, wherein a workload can easily be moved between virtual environments without interrupting service. 

Virtual server challenges

Generally, the advantages of server virtualization far outnumber the disadvantages. This is not to say that there aren’t any challenges that are associated with virtual servers, the most common being resource hogging. Since virtual servers are reliant on the processing power of the underlying physical machine, too many virtual servers operating on a single bare-metal server or server network can result in decreased performance. While the capacity of any physical server informs the capacity of any virtual servers it may be hosting, server crowding can be easily remedied by migrating heavy workloads to different physical servers or through virtual private servers.

Virtual private servers and web hosting

A virtual private server (VPS) is one type of virtual server offered by hosting service providers that guarantees a certain amount of the physical machine’s CPU bandwidth will be dedicated to a given virtual server. Cloud services providers commonly offer virtual private servers at various pricing tiers as a way for businesses to enjoy the benefits of a dedicated physical server without committing to an actual physical machine. Full virtualization optimization allows organizations to customize their virtual private servers with features like load balancers, SSL certificates, firewalls and more.

Virtual servers versus virtual machines

While both virtual servers and virtual machines (VMs) use virtualization and hypervisors to create unique, partitioned virtual environments, there are key differences between the two.

As explained, virtual servers are used to replicate physical, bare-metal servers for applications like web servers, domain name servers, proxy servers and application servers, among others. Meanwhile, virtual machines are used to create virtual representations of physical computers. Cloud environment providers typically offer virtual desktops to emulate the functions of underlying hardware while simultaneously isolating the virtual machine from the host computer.

Because virtual machines are isolated from the host, they can also run their own operating systems, regardless of whatever operating system the host computer is running. For this reason, virtual machines are a useful tool for testing apps across different types of operating systems. Additionally, virtual machines can be quarantined from the larger network ecosystem, providing a level of protection and safeguarding sensitive cybersecurity incidents.

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What are virtual machines (VMs)?

A virtual machine is a virtual representation of a physical computer and the compute units for the first generation of cloud computing.

What is virtualization?

Virtualization enables the hardware resources of a single computer—processors, memory, storage and more—to be divided into multiple virtual computers, called virtual machines (VMs).

What is a virtual private server (VPS)?

A VPS, or virtual private server, is a form of multi-tenant cloud hosting in which virtualized server resources are made available to a user over the internet through a cloud or hosting provider.

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The VPS hosting solutions inside IBM Cloud consist of cloud-managed compute hosting hardware, software integration and data migration support. Choose from a variety of virtual server, networking and storage products to build the solution that’s right for you.

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