Ad Hoc Designed Infrastructures - Do They Still Make Sense?

The topic in this article is something that I have been thinking about for a while. It's about the methodology, the patterns, the habits - if you will - associated with how new IT infrastructures are being assessed, designed, sold and - in the final analysis - acquired by end-users for their datacenters. While it might not make a lot of sense to you initially, please bear with me as I go through my "internal mental brainstorming." It seems long but, as usual, it's full of pictures.

The Italian market is pretty interesting: the vast majority of the customers are (very) small organizations distributed across the entire territory. We also have a few medium-sized businesses (although not the core economy of the country), and then we have big organizations (a mix of public customers and privately held corporations). To turn this into IT terms, the vast majority of Italian customers' datacenters are very small - in the range of 5 to 15 x86-based servers. We then have customers - such as medium-sized businesses, big banks and big public organizations - that have hundreds to a few thousand x86-based servers. Having spent most of my IT career focusing on the optimization of the x86 infrastructures, I had to deal with all these scenarios above so I think I have a pretty complete view of the spectrum. This article is going to discuss specifically a couple of points that I had to deal with during the process:

1. The assessment of the legacy infrastructures from a capacity and characteristics perspective.
2. The design of the target architecture of the virtualized infrastructures.

These are two different aspects, and they could deserve a dedicated discussion, but I am trying to cover both in this article anyway. 

Assessing and Designing Optimized x86 Infrastructures for the Small IT Shops

At the very beginning of the virtualization era (around 2002-2003), I was using a pretty standard methodology that would require the analysis of the current datacenter in terms of number of physical x86 servers deployed, their hardware configuration and their usage (average at least, historical at best). You would then take the data and work through them to get to a specific hardware sizing that was capable of consolidating those physical servers onto a lower number of physical boxes. This has worked pretty well until a few months ago when I sat down with my good fellow Maurizio Benassi and we drafted a brand new methodology for sizing. It all started with a joke:

"The majority of customers could be consolidated on either one single mainframe (which never breaks), two Unix boxes (which very rarely break) or three x86 servers (which happen to break from time to time)."

A further analysis of the patterns resulted in an updated joke (err: statement) regarding the new pragmatic methodology:

"One x86 server could sustain the whole workload, the second x86 server is configured for high availability, the third server is used to sleep well at night."