[Beowulf] What is the right lubricant for computer rack sliding rails?yh

Lux, James P james.p.lux at jpl.nasa.gov
Mon Feb 9 15:40:00 EST 2009

> -----Original Message-----
> From: beowulf-bounces at beowulf.org
> [mailto:beowulf-bounces at 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.


* 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)


Beowulf mailing list, Beowulf at beowulf.org
To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf

This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.

More information about the Beowulf mailing list