Virtualization products compared

The 3 major players, at the moment, in the virtualization market are VMware, Microsoft and Citrix.

The 3 companies are ranked in the above order with VMware leading the way due to its vast experience in the market. In this post I will be looking at the different products the vendors offer and their most important features.

ESX 4 Server (V-Sphere)

  • Runs only on 64bit hosts.
  • Memory over-commitment is a huge feature which is unique to V-Sphere. This allows the administrator to allocate VMs a larger amount of memory than the physical host actually has.
  • It is available on the market in 3 versions:
    • ESX full
    • ESXI
    • ESXI free

VMware server

  • It is deployed as a management layer virtualization product (hosted).
  • It can run on both Windows and Linux.
  • It can host both 32bit and 64bit VMs.
  • Since the release of ESXI free the use of such virtualization product has gone downhill.

MS Hyper-V

  • Runs directly on the HW just like V-Sphere.
  • Can be administered centrally via “System Centre Virtual Machine Manager” (aka SVCMM).
  • Can only run on 64bit hosts just like V-Sphere.
  • Can run both 64bit and 32bit VMs.
  • Can be obtained as standalone, which is free, or in various versions of windows 2008.

MS Virtual Server 2005 R2 SP1

  • It is free software.
  • It is deployed as a management layer virtualization product (hosted).
  • Runs on Windows 2003.
  • Has a web interface which integrates with “System Centre Virtual Machine Manager” (aka SVCMM).
  • It has the capability of running a larger number of VMs when running on a 64bit host.
  • Only runs 32bit VMs.

Citrix Xen Server

  • It is free software.
  • It is enterprise virtualization software (runs straight on the HW).
  • 64bit Hypervisor.
  • Runs both 32bit and 64bit VMs.
  • It offers a huge amount of features, comparing to VMware and MS, for a free edition.

This link has a very good table that compares all 3 vendors and what they offer:
http://www.boche.net/blog/index.php/2009/04/22/vmware-vsphere-cheat-sheet/