Troy has an interesting take on what's going in server consolidation and virtualization and how it impacts configuration management. I like the point he is making that while the number of servers is being reduced, the number of services is going up.
But I have a bit of a different take on what he thinks that implies. Here's a quote:
For Example: Lets say you have a physical server (a component of your Infrastructure Service called Hosting) which hosts three different virtual servers each suppling the processing support for a business application service. However these three application services have very different levels of business criticality. Now lets say a change has to be made to the parent physical server to address a patch level. What risk level do we assign to this change? The answer of course is that the physical server must inherit the highest risk level of the services that depend on it. This means that we maintain a clear understanding of what each component does in relationship to business outcome.
This is interesting and true. But may not be that important in the future from a service catalog perspective. Here's why. It assumes that a) I own that infrastructure, b) that a failure there impacts my business service. This is becoming less true everyday because of the new grid computing, on demand infrastructure. I've been playing with Amazon's Elastic Cloud Computing and S3 and talking to some companies using it.
Amazon's ECC allows you to load a server image to a computer cloud and the ratchet servers up and down as you need them. Need 20 servers, ratchet up. Need less an hour later? Ratchet down. This is done at a fixed fee per cpu hour and bandwidth transfer. Essentially, the cloud is the datacenter; I don't own it, I don't have any visibility in it, it's completely virtualized. And the same with storage and message queing services. Amazon offers no SLA's today, other than their reputation for uptime.
So yes, some amount of configuration may be needed. But more importantly, we need to figure out what the service is from the point of view of the customer because this is what they buy. A friend of mine is working at web 2.0 company that uses Amazon's ECC, but they themselves are a service provider for other web companies! This is infrastructure virtualized and controlled through commercial agreements. It all works because each company has an incentive to stay in business.