> -----Original Message----- > From: beowulf-boun...@beowulf.org > [mailto:beowulf-boun...@beowulf.org] On Behalf Of Robert G. Brown > Sent: Monday, February 09, 2009 3:15 AM > To: Mark Hahn > Cc: Beowulf List > Subject: Re: [Beowulf] What is the right lubricant for > computer rack sliding rails?yh > > On Sat, 7 Feb 2009, Mark Hahn wrote: > > >> The tricky thing with the "rack rail" approach (which we > use a LOT at > >> JPL) you give is that if the units have cases that are also full > >> height, you can't stack one unit directly above another, > so you have to leave a 1U gap. > > > > OK, this may gross you all out, but why mount 1U's > individually at all? > > I'm a lazy slob, but I have several 1U's stacked on top of > each other > > - after all, how often will you really need to get the > non-top one(s) out? > > depending on how fancy your servers are, saving the price of a rail > > kit might even make $ense. admittedly, I did this on an older > > cluster, designed-for-cheapness cluster because I couldn't > be bothered > > to order and assemble the rails... > > > > wait, how about this: consider stacking 1U servers on their side. > > you'll still be able to pull them out if you want. would > the hardware > > care about the orientation? muffin fans wouldn't, and > disks out to be > > able to handle it. come to think of it, there's no reason > to think of > > this wrt conventional 19" racks. you could just weld > together a frame > > of nice tough angle-iron supports (of whatever length you > can manage > > to support the load without sagging embarassingly ;) > > It's really the difference between a HPC cluster and most > business clusters. HPC nodes go in, and they don't come out. > Unless they break, and if you get high quality nodes, > breaking is unlikely. > > > think of it this way: by omitting a proper rack and rails, > you could > > probably save something like $60/node. can you think of a > better way > > to spend $2400 (per rack)? admittedly, that's probably > only a few percent of total cost. > > And don't forget the ten or twenty minutes of human labor > required to mount the nodes on the rails, one at a time. > Take rails out of box, out of back. Pull out bag of screws. > Ditto the node. Set node on side.
For truly expedient... Stack all chassis in rack with no screws. Front panel ears in front of side rails. Put 6 foot length of angle iron down front of rack in front of all chassis. (or a wood 2x4 of suitable length) (or two pieces of wood, one on each side, covering the rack ears) Ratchet strap* around entire rack, about 3 feet from floor. Tighten. Second ratchet strap around entire rack, about 5 feet from floor. Tighten. Done** * Duct tape could be used as well. ** (the rack will almost certainly be bent by this, and not usable for any other scheme, but hey, if you never have to take the things out, who cares) Jim _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
