Dave Hitz, co-founder of Network Appliance, talks about two different data centers in his blog with different needs, one who has had success with VMware server consolidation, and the other who hasn’t virtualized because they are at full utilization and have good capacity management systems.
The first punchline at the end of the article is that, in fact, company #2 does have a lot of server consolidation candidates in their business, just not in their primary business application. The second punchline will come later, when company #2 realizes that VMware is about more than consolidation and provisioning — and in fact VMware is a rich platform for resource management, security, business continuity, lifecycle automation,
and enterprise desktop management.
The first customer—who asked me to describe his company as "a large UK based Telco"—used VMware to consolidate 502 windows systems onto 25 blades. He freed 173 racks worth of space. He cut power by almost 450 KW per month and reduced his power bill by $50,000 per month, not to mention reduced service and support. In all, he expects to clear 345 racks and replace them with 20 racks, with a full return on investment in less than a year.
The other customer explained why VMware won’t help him at all. He runs a large internet site with hundreds of web servers—lots of Linux and Apache. He has a load balancing methodology that lets him saturate his servers. (In his case, the systems are actually memory limited, because they cache the most commonly used data. In other environments, CPU is the limiting factor.) He argues—correctly in my view—that VMware wouldn’t help him consolidate at all, because he has no spare capacity. VMware’s management capabilities could be of some use, but he already solved those problems, so he isn’t looking for any help there.