Running Exchange on VMware
VMware has pushed the idea of virtual Exchange servers for several years. VMware even wrote a white paper on this topic, Running Microsoft Ex- change Server in a Virtual Machine Using ESX Server 2.5 (http://www.vmware.com/vmtn/resources/510). VMware offers tools such as VMotion to move servers within a virtual environment and VMware VirtualCenter to manage the VMware ESX Server platform and deploy new virtual servers configured from prebuilt templates. Although the white paper outlines the advantages of the virtual server approach, VMware acknowledges that Microsoft doesn’t support Exchange 2003 running on a VMware platform and that moving overloaded Exchange 2003 servers into a virtual environment is unlikely to return great benefits.
VMware claims that it can work around Microsoft’s support policy by deploying active mailbox and other Exchange 2003 servers on a physical system, while keeping passive virtual servers available as a fallback if a problem occurs with a physical server. VMware’s workaround is certainly an interesting approach: Microsoft will support Exchange 2003 running on the physical servers, and customers will realize some cost efficiency and resilience by deploying passive back- up servers. However, because you need to use clusters to create active and passive Exchange nodes, deploying Exchange 2003 according to VMware’s recommendations increases cost and adds support problems to the existing complexity of cluster deployment and operation, outweighing most of the benefits achieved by using passive backup servers.
Should You Wait?
Configuring complex storage remains
a challenge for virtualized environments today. So unless you plan to
support only a small number of concurrent users, I recommend that you
stay away from virtual Exchange 2003
mailbox servers. Exchange 2003
servers that generate smaller I/O
loads, such as bridgehead or mail
hygiene servers, are better candidates
for virtualization. In part two of this
article, I’ll discuss deploying Exchange
2003 in a virtualized environment.