Monday, July 30, 2007

IBM p660 7026-6H1 RAM Installation

We have an IBM p660 model 7026-6H1 that required 2GB more RAM. The system started out with 2GB in it. A couple years ago, we had IBM install 2GB more. At that time, IBM was still selling the new DIMMs. We bought it from them and the CE came in to do the installation.
Due to application upgrades, we needed 2GB more. IBM no longer sells new memory for that box. (By the way, have you ever seen a company retire hardware faster than IBM?) Off to the refurb market, I purchased 2GB more (4 x 512MB DIMMs FRU 0000033P3584). The DIMMs must be installed in quads.

I searched the 'net for DIY installation instructions. Ha! IBM keeps a tight lid on such documents. Sun Microsystems, for contrast, keeps an online library of every document under the sun, no pun intended, and ships out CDs with the servers with animations of how to install whatever you want to. Not IBM. No sir-ee, that there computer is far to complicated for anyone except a $300/hour IBM engineer to work on. We could show you the documents, but you'd only hurt yourself.

Anyway, I was watching when the CE installed the RAM a couple years ago, so I figured I could take a pretty good whack at it. I scheduled the downtime and grabbed my toolkit and static strap.

Our p660 is a multi-processor box. There's a special rule about those boxes with single processors and how much memory they can hold, so I can't help you there. Our system is a four-way and the CPU shelf (not the I/O shelf) contains a 16-slot memory expansion board.

I had to unplug a couple of items like the keyboard and mouse to get the CPU shelf to slide out the back of the rack far enough to get the top off. Two easy screws, no problem. The RAM expansion board is on the right, looking at it from the back. I think there are two in there, actually. I pulled up on the tabs for the leftmost one. It had sixteen slots, eight already occupied with 512MB DIMMs - two fore and aft slots in each of columns 1, 2, 7 and 8 from left to right as viewed from the rear. The memory has to be installed in sets of four, symmetrically left and right about the center line. (I know this because I installed the DIMMs symmetrically forward and back and it no worky.) I put a DIMM in the fore and aft slots in columns 3 and 6 and booted to see through "bootinfo -r" and "lsattr -El sys0 -a realmem" that the system was now showing 6GB installed.

DIY is much cheaper than purchasing an MES to have IBM do the installation. This of course doesn't address the issue of how IBM will feel when/if RAM goes bad, I call them for contract service, and they find refurbished RAMs in the box installed by "unqualified" personnel.

Gotta' Start Somewhere

I depend on Google and the Internet to do my job. I'm a systems admin and it's hard to remember how I ever did my job without the ability to search the Internet and find people having problems just like me and their solutions to those problems. I suppose I did it more slowly. In fact, I was not a system administrator when the web was born, so that's probably the reason I can't remember what it was like.

Around 1993, when I started playing with Mosaic and installed my employer's first web server and homepage, I was just the help desk guy and also helped out with some systems stuff, some network stuff, and some database programming stuff. Now, fourteen years later (yikes!) our web page has long been in the hands of others, but the web server itself is still mine. I'm now the Unix (and sometimes VMS for what we have left) guy around here.

This blog will have some of my notes from work in it. You will likely see the more interesting, difficult, or entertaining computer problems I encounter. I have found countless solutions to problems on the net, in tech forums, help pages, and blogs like this. I've always felt like I should give back a little. This blog is my modest attempt to do that.

Of course, it's actually a selfish endeavor as it will help me remember what experience I've had and will give me an easy-to-search resource of my own past solutions if the problems pop up again.