I've worked for numerous companies that were IBM customers. For several years I worked for IBM in Boulder, Colo. I currently work for an IBM business partner. Through all this time, I've been happily using IBM racks with IBM servers. Sure, there were other servers running other operating systems that used different racks in the various computer rooms, but the IBM servers all lived in IBM racks.
I was recently on a raised floor at a server co-location company and watched IBM customer engineers move a POWER5 Model 570 from an IBM rack to a non-IBM rack. To install the server, they had to carefully measure its required depth. To make the flex cable on the front of the machine fit into the rack, they had to modify the side of the rack due to some protruding metal on the side doors that was interfering with the flex cable. Obviously, the whole operation took longer than a regular rack install into a standard IBM rack would have taken.
While they got the server to work in the non-IBM rack, it wasn't an ideal situation. The power distribution units in the back of the rack were rotated compared to the IBM rack, and the plugs were oriented so that when the servers were plugged in, power supplies and PCI cards couldn't be swapped without removing the entire PDU first.
So why go to this trouble? These non-IBM racks are taller and have a smaller footprint than the previously used IBM racks. When you're paying by the square foot, you want to squeeze in as much equipment as you can. By using extra space at the top of the rack, the co-locator could fit more equipment into its floor space. I can certainly understand that with several taller, narrower racks, you can wedge more racks into a row of hardware, and that can translate into more revenue for the operators of the shared environment. (This might not matter so much in a customer-owned data center, but in this shared environment, it's critical.)
One of the facility managers said that IBM just doesn't get co-location. He argues that every other vendor can make its equipment fit into these racks, why can't IBM?
My take is that IBM engineering designs IBM racks with IBM hardware in mind. They're rugged. They're built to fit without modification, and they're built so that parts can be easily hot-swapped in and out of the machines. If IBM racks don't fit nicely into your cookie cutter server room that was designed with non-IBM servers and racks in mind, if they're wider than other enclosures, then maybe it's time to rethink the design of the room. The problem as I see it is that many customers think that everything is the size of an x86 machine. However, they should plan for equipment of other sizes. It's not necessary to redesign the computer room--but maybe designating an aisle for nonstardard-sized racks would give them some flexibility.
The thing is, the greater serviceability of IBM solutions is well worth the sacrifice of some floor space. IBM engineering designed and built its racks with IBM servers in mind. Using PowerVM and IBM Power Systems servers, you can consolidate multiple large workloads onto a much smaller footprint. And isn't creating the smallest footprint the goal here? Yes, IBM racks might take up an extra square foot or two compared to non-IBM racks, but this should be easily offset by an overall reduction in server hardware.
I believe IBM keenly understands co-location. They've given me hardware that I can easily carve into
multiple LPARs per physical frame, which allows me to consolidate workloads. The technology is very forgiving and flexible--as workloads grow and change, it's very easy to use a dynamic LPAR operation and make the adjustment.
Ultimately of course, the customer is always right. So if you need to make your server fit into a smaller footprint on your raised floor, you can and should do so. But first, reconsider what you're giving up by making this change. Saving physical space doesn't always equate to saving money.