Server virtualization is now an essential element of modern enterprise IT infrastructures, enabling multiple virtual machines (VMs) to operate on one physical server using a hypervisor that abstracts away its underlying hardware so VMs can share resources such as CPU, memory and storage.
Powerful physical servers often possess excess processing and memory capacity that would go unused without server virtualization technology. This technology helps organizations consolidate their IT infrastructure, optimize resource utilization, scale more easily, and increase scalability and flexibility.
Type-1 Hypervisors
Hypervisors have become an integral component of virtual machine management on personal PCs and within businesses alike, providing IT professionals and other business leaders the ability to utilize hardware resources more efficiently, reduce costs and provide increased flexibility.
Type 1 hypervisors, also known as bare metal hypervisors, operate directly on physical server hardware without an additional OS layer, enabling optimal resource allocation while reducing overhead and latency. They’re most often utilized in enterprise environments requiring high performance such as data centers or extensive virtualization deployments.
Virtual private servers (VPNs) also allow streamlined access to guest OSs running alongside the host operating system, making them an attractive option for business users who must operate across multiple platforms, such as engineers running software tests on a Windows desktop while working from home, or security analysts analyzing malware. Many include additional productivity tools which allow end-users to cut, paste and access host OS files and folders without relying on special remote applications.
Type-2 Hypervisors
Type 2 hypervisors use their host operating system to interface with physical hardware, resulting in higher latency than Type-1 hypervisors; hence their greater utility for end-user productivity (for instance when developing software on Linux desktop using speech dictation on a Windows desktop).
Type-2 hypervisors also pose greater security risks, since an attacker that breaches the host OS could exploit this vulnerability to manipulate VMs within it. They’re less efficient as Type-1 hypervisors, too; accessing hardware resources requires going through the operating system directly – leading to performance issues like lag.
Type-2 hypervisors are convenient and straightforward, with minimal setup requirements. Installed as regular applications on the host OS, virtual machines launched through them appear as windows within that OS. They are capable of using hardware acceleration technologies when available but typically fall back on software emulation when native support is unavailable.
OS-Level Hypervisors
Hypervisors are software layers that enable multiple operating systems to utilize one physical hardware in a controlled and isolated fashion, enabling the computer hardware to manage more workloads simultaneously while making more cost- and energy-efficient use of its resources.
Traditional PCs were limited to running one OS per machine and sharing its resources among applications running on it; although this made hardware more stable, it squandered computing power. Hypervisors allow one physical computer to host multiple virtual machines (VMs), smaller instances of itself that share only some physical hardware resources – including processors, memory and storage space.
Hypervisors must perform several process-intensive tasks to manage virtualized environments, including hardware emulation. This requires a hardware platform specifically designed for virtualization with features like AMD Virtualization Technology or Intel Virtualization Technology; such technologies increase server performance as well as practical number of VMs that it can host.
Consolidation
Server virtualization enables one physical piece of hardware to host multiple virtual machines (VMs) that operate different applications and workloads on separate operating systems, providing for efficient use by each VM as if it were its own computer.
IT shops use server virtualization to consolidate the number of physical servers required to support their organization, improving resource utilization and potentially cutting costs at once.
Modern physical servers typically possess more processing and storage power than is necessary for any given workload, meaning the excess resources go unused. But these powerful pieces of hardware can realize their full potential when utilized by multiple VMs running concurrently on it.
Server virtualization tools allow businesses to rapidly upscale or downscale resources based on business requirements without purchasing new hardware. Utilizing features like prioritized VM restart, they can ensure availability during maintenance windows without disrupting critical workloads. Prior to adopting server virtualization technologies, organizations should have an established plan of action and project roadmap in place.