Rolling a rack on carpet

David Mathog mathog at
Fri Oct 25 15:01:06 PDT 2002

> I was thinking about how you switch back on, post pulling
> the power cord out.  When I put mine back in they don't all start
> back up until you press the little ATX on/off button on the front.
> I guess it may be a BIOS thing,

Definitely a BIOS thing.

Unfortunately it's all or nothing, and I often want a 
delay.  That is, after the power comes back on the slave
nodes I'd like them to wait a few minutes before powering up
so that the master node will be all the way up first.  With
enough nodes it would be best to stagger the start up too. 
And the master node might want to wait a minute or two
itself so that the routers will have come up.  I wrote
to Phoenix/Award asking for this feature but who knows
when/if they'll ever put it in.

This can be done trivially and nearly as well with lilo/grub by
setting the timeout values to something fairly large on the
slaves and something not quite so large on the master.  It's
"nearly" because all the nodes will still power up as soon as
power is reapplied.  If it was in the BIOS, power up could be
staggered as well.

I suppose you could set the slaves to boot when
signaled through the ethernet card for those NICs/BIOS's that
support that function.  Then the master could boot the 
slaves at its leisure.


David Mathog
mathog at
Manager, Sequence Analysis Facility, Biology Division, Caltech

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