[jan-jaap]

I have some 25 SGI systems and in my current computer room, I took the "everything is ready to run at all time" route. With that many systems it escalates quickly:

1. Power. SGI systems consume a decent amount of power even when powered down. Multiply by 25 and it will cost you. Also, I believe that having that many systems that are that old permanently connected to power is a fire hazard. So I can switch power to each remotely using PDUs.
   
2. Network. In my case both ethernet and fiber (FDDI). Storage (FC). Serial console. The amount of cables is enormous. I've got nearly a kilometer of network and glas fiber cable in my computer room. If you don't want to trip over bundles of cable the size of your fore arm you have to plan this properly. Browse THIS thread to get an idea.
   
3. Keyboard/video/mouse. I haven't even solved this one yet. I have a "workstation" rack with a lot of my systems on the shelves. They range from a Personal IRIS 4D/35 to a Fuel, which means I'd have to deal with "4D" serial keyboard/mouse and PS/2, and analogue and digital video signals using at least two or three different sync methods. While keyboard/mouse adapters for the old systems exist, my experience with those in combination with a KVM has been disappointing
   

In my old computer room (and when I had less systems), I would simply pull the plug on systems I didn't use. I had them clustered on/below a desk, and if you group them a bit by age then sharing a keyboard/mouse/screen isn't too complicated.