What is Server Virtualization Software?
Server virtualization software allows multiple operating systems to run independently of each other on a single machine in a data center. Virtualization software called Hypervisors encapsulates a guest version of the operating system and emulates hardware resources. In this way, virtualization software uses hypervisors to allow multiple server instances to run on a single machine.
Virtualization software reduces the need for physical hardware systems. The resulting increase in resource utilization lowers server costs. Containerization, however, popular since the emergence of Docker, supplies an alternative to server virtualization for organizations that only require the use of one operating system. Containerization achieves greater efficiency than server virtualization software by foregoing a hypervisor and sharing a single instance of the operating system and running on the “bare metal” of the server.
Server Virtualization Software Features & Capabilities
Server virtualization software provides these common features:
Type 1 or type 2 hypervisor
Run multiple virtual machines using different OS on same server
Automated virtual machine provisioning
Manage remote physical locations, branch locations with rapid provisioning
Server health monitoring, performance bottleneck, workload rebalancing
Centrally control and optimize virtual machine environment
Patch or backup virtual machines without interrupting service
Migrate live virtual machines between hosts during scheduled maintenance
Hypervisor-level security, including antivirus and anti-malware
Secure apps and infrastructure with guest operating system lockdown
Auditable activity, performance log
Types of Virtualization Software
Virtualization software can be distinguished by the type of hypervisor they utilize. Hypervisors are an important part of virtualization software as they allow a host machine to manage multiple virtual machines.
Type 1 hypervisors are installed directly onto the server. As a result, type 1 hypervisors provide high efficiency and stability. Server virtualization software that uses a type 1 hypervisor is ideal for larger operations that use many server instances.
Type 2 hypervisors are installed on top of a server’s operating system. Virtualization software using a type 2 hypervisor is easier to install and manage for smaller projects but can become more difficult to manage as projects grow.
Server virtualization inherently reduces data center costs by improving resource utilization. Virtualization software subscriptions are available at a monthly or (more common) annual cost, with reduction in cost for up-front multi-year commitments. Subscriptions are priced according to managed hypervisor socket pairs, or per number of physical processors featuring virtualization. Free trials ranging from 30 to 60 days are available from some vendors. Server virtualization is also sometimes offered with on-demand pricing (e.g. compute capacity per hour).
VMware offers a very comprehensive selection of virtualisation products, with Fusion for the Apple Mac and Workstation Player for the PC.
Despite the name difference, these two products offer effectively the same solution, though tailored to each host OS.
For the Mac that includes a neat ‘Unity Mode’ that enables Mac OS to launch Windows applications from the Dock and have them appear like they’re part of the host OS.
Workstation, as the version numbering suggests, is a more mature product and delivers one of the most sophisticated VM implementations seen so far.
Being one of the few hosts that supports DirectX 10 and OpenGL 3.3, it allows CAD and other GPU accelerated applications to work under virtualisation.
Workstation Player for Windows or Linux is free for personal use, though Pro is required for business users, and those wanting to run restricted VMs created using Pro or Fusion Pro.