25:1 seems a bit high
The trend toward more VMs per server is clear. According to a recent ESG research survey, 24 months from now, nearly one-third of organizations (31%) expect to host at least 25 virtual machines per physical server. Based upon qualitative interviews with end-users, ESG believes that these numbers are somewhat skewed by server virtualization usage in test and development where virtual to physical server ratios tend to be much higher than in production environments. On average, it is common for us to see 5:1 and administrators are grinning ear to ear with their success. 25:1 seems a bit aspirational to me and it has nothing to do with any technology barriers. Achieving higher consolidation ratios requires confidence in your environment and in order to gain that confidence, you need organizational alignment, visibility, reporting, automation, and management tools. I have no doubt that some will achieve 25:1, but since most of the deployments we see are still very focused on consolidation and they haven’t invested the time into better management processes and organizational adjustments, it will be difficult for them to scale to 25:1.
