The hostname of a server should be recognizable. It should tell you exactly what you are doing with that server. However, it also has to be unique within your network. Database023 and Web46 don’t cut it in my opinion. (Not that any of my projects are of that scale.)
I tend to name my servers after characters in anime I’m currently watching. This does give them a unique spin (at least for me, and I’m the only one ever working on them) but it doesn’t help me figuring out what they do. I usually have to log in for that.