I was recently introduced to some practical usage of vCenter tags. I used tags to build a fairly easy and dynamic set of sources for Veeam backup jobs, but before I get into that, I want to explain tags a little bit for those who are not familiar with them.
Tags are something that are pretty easy to understand conceptually. You create a category which contains a few tags. An object can receive one or multiple tags from a given category. Tags are managed by vCenter, not by vSphere, so require a license that provides vCenter for management. That’s a pretty simple explanation and list of requirements.
A Tag Category has a collection of Tags available within it. If the Category is “single cardinality”, it means that an object can only be assigned one tag in the category. This might be good for a category associated with ownership or recovery point objective (RPO). A Category can also be “multiple cardinality”, where a single object can be assigned multiple tags in a category. This would be helpful to associate applications with a VM, or a list of support teams that need notified if there is a planned impact or outage.
I’m going to show you how to manage Tags and Tag Categories with PowerCLI (Specifically with the PowerShell ISE and a profile to load PowerCLI), but you can manually create and manage them through the vSphere Web Client, under the Tags item on the left hand menu. You can create and delete and rename tags and categories there all day long, and you can right click on an object almost anywhere else and select Edit Tags to edit the assigned tags on it. When you view most objects, you’ll see an area in the Summary tab labeled Tags that will display and let you manage assignments.