I want to know if all vendors rack servers are compatible with all rack chassis?
Apart from the height requirements there are three important points to consider.
- Round or square holes in the rails.
- Depth of the rack.
- Whether the mounting rails are compatible with your server mounting hardware, such as slides.
Although I've intermixed devices and racks with round and square holes it's much easier if you have the correct one. Square is by far the most common.
Rack mount devices can vary considerably in their depth. I've had to take the back door of racks before because a new server is just a tiny bit too long. Work out the greatest depth your devices require and then add a bit more to that to be safe.
With mounting hardware you will sooner or later come across stuff that's supposedly designed for "standard" racks (there's actually no such animal) but you won't be able to mount it without modification. There's precious little you can do about that other than be prepared for it. I've been fortunate enough to always have access to metal working equipment when having to deal with this little issue, resorting to cutting and welding on more than one occasion.
It's not so much the servers as the rails that you have to be concerned with.
If you stick with good-quality racks and name-brand servers, you probably won't have any problems. If you start getting white-box rack servers, the rails they come with might not fit so cleanly.
For servers, stays away from racks with tapped holes or round holes that use caged nuts. Stick with square holes.
Heres a nice Howto:Racks and Rackmounting article by Matt Simmons that you might want to take a look at:
If you have a standard rack chassis, the short answer is yes.
If you have a non-standard rack chassis, it will depend. In a previous colo, we had a bizarre and very cheap chassis that would not allow us to rack Dell and HP equipment. The door also "fell" off so we ended up switching it with standard racks.
Chances are if you can rack one, you can rack all.
Check the length, especially with regard to storage arrays.
I agree with checking the length especially if Your looking at Mixing Unix and Wintel servers as the depth of the rails can differ vastly and it may not be possible for certain servers to be mixed with other servers . Firewall devices are very guilty of this too as I've seen several with non standard depths which required servers to be racked in other cabinets as the rail length wasn't big enough for the servers to be racked after the Cabinet had been refurbished to work with the firewall devices .