[geeks] Need refs for the clue-impaired on redundant PSUs

[Phil Stracchino]

velociraptor wrote:
> Anyone have any good references out there regarding how
> redundant PSUs generally work?  I need something, preferrably
> from "experts," to give to the clue-impaired.
> 
> Some *ahem* people (I use this term loosely) are having issues
> with hitting the ceiling on their UPS and incoming power and seem
> to think removing the redundant PSUs on their existing servers will
> give them room to add more servers.

I think it's implementation-dependent.  Some run both PSUs at part
output and ramp up the good one if the other fails.  Some run one at
full power, idle the other, and ramp up the other if the first fails.
Some keep one offline on standby and fast-switch to it if the first
fails.  (Bummer if the backup's dead and you didn't notice.)


-- 
 Phil Stracchino       phil.stracchino at speakeasy.net
    Renaissance Man, Unix generalist, Perl hacker
 Mobile: 603-216-7037         Landline: 603-886-3518