IT managers looking to unleash virtualization technology in their production networks should anticipate a major overhaul to their management strategies as well. That's because as virtualization adds flexibility and mobility to server resources, it also increases the complexity of the environment in which the technology lives. George Hamilton, director of Yankee Group's enabling technologies enterprise group, recently talked with Denise Dubie, Network World senior editor, about what network managers need to do to get ahead of the management challenges that virtualization could introduce to their networks. What follows is an excerpt from their conversation. To hear the full discussion, check out our podcast.

Virtualization technology is expected to start moving onto production networks this year and next. How should network managers prepare?

We've dealt with physical-server sprawl and we know what that is. Now we have virtual-server sprawl. You can very quickly deploy virtual machines into an environment, and it's very easy to get virtual-machine sprawl. You can end up with capacity issues and resource allocation issues, so a lot of the initial challenges are around how to optimize the physical infrastructure for all the virtual machines.

What will help prevent this virtual sprawl from affecting network performance?

It's getting visibility into the behavior of the virtual machines that are running in production. If you think of VMware's VMotion technology, which allows you to move live servers around in real time, there are still some manual processes for being able to identify virtual machines that may be performing badly and trying to correlate that with how the physical servers are performing. IT managers need to orchestrate the alerts and then be able to move VMs to the right place at the right time to optimize performance and capacity.

Why won't the tools or processes network managers are using today stand up in this virtual environment?

It would just be impossible based on the number of alerts -- which could be hundreds to thousands of alerts on performance issues. To be able to manually reallocate resources, that is just not feasible and it goes against the whole value of virtualization. You would end up having to provision a bunch of overhead so that you could move the VMs around successfully without interrupting anything. And that defeats the whole purpose of trying to optimize the infrastructure.