Warren Estes explains how he keeps track of his servers using a Central Management Server:
We use a CMS server for each domain and I can’t imagine life without it. Kind of like when I discovered Amazon prime, or bought my first memory foam mattress.
The real magic of a CMS comes from being able to push jobs, or evaluate policies, on any server (targets) you want.
You can also execute T-SQL against all, or a subset of servers with either registered servers or CMS.
There are some caveats to look out for like collation differences and version specific DMVs when running queries across instances. Also security needs to be addressed. However, that is outside the scope of this post. You can find that information in the links in the first section.
I liked CMS when I had to deal with a dozen instances. With hundreds of instances, I wouldn’t want to administer anything without one.