Decommissioning NT4 Domains - Part 1
Posted in Windows Server by Ben Christian on April 6th, 2006 I’m in the process of decommissioning three NT4 domains as well as some legacy servers. The domains had previously remained in place as we had some Windows NT 4.0 EIC telephony servers and an underlying Exchange 5.5 infrastructure that were dependant on them (EIC uses unified messaging).
I’m going to spread this post over more than one entry, the first part will cover the planning stage.
Planning
Identifying the domain’s dependencies
The first step in planning the project was to determine what was actually dependent on the domains. Although I knew that the EIC and Exchange servers relied on the domains, there were some servers and service accounts that were still in use; these needed to be documented and assigned an action. I created a MindManager map which listed each domain as a main topic, and each server within the domains as the immediate child topics. Branching out from the servers was each service, server, or user group that was dependent on these servers. I then used map markers to assign an action to each dependency. This allowed me to start thinking about the order in which I could remove servers. Naturally I can’t include the actual document for security reasons, so I’ve created a basic example of the dependencies mind map. It contains enough detail to give you the general idea, but it’s far from complete.
Going through this exercise was very valuable; it’s something that I plan to do for each environment that I work in with in future.
Action Plan and Project Time Line
After creating the dependencies map, I created a Microsoft Project document. The nice thing about Ms Project is that you can assign “predecessors” for each task. This allowed me to translate what I had identified as dependencies in the mind map into an ordered list of tasks with predecessors. For example, the server that hosts the EIC database cannot be decommissioned prior to the actual EIC server; therefore the task to decommission the EIC server became a predecessor of the task to decommission the EIC database server. For each server to be decommissioned, I allocated a date for a final backup and to shut the server down. I planned the actual hardware to be decommissioned several weeks after the server is shut down to leave enough time to back out.
