[Nut-upsdev] External Devices

Arjen de Korte nut+devel at de-korte.org
Fri Dec 1 21:06:09 CET 2006

Philip Ward wrote:

> Thanks for your replies. When first attempting to configure nut I considered 
> using the current master/slave plus MINSUPPLIES to accomplish the task, but 
> it is ever so slightly inadequate.
> Imagine 4 UPSs. Two powering a server and two powering a disk array. You would 
> set MINSUPPLIES to 2 since each device requires at least one UPS. However, 
> there is no logic that says "only shutdown if the two UPSs that have failed 
> are both powering the same device". If 2 UPSs fail then it could be one each, 
> or it could be that both UPSs powering the disk array have failed.
> My changes enable you to say that the server needs a minimum of 1 supply and 
> that the disk needs a minimum of 1 supply.

I appreciate the problem you're trying to solved here, however I'm not
convinced that this is the proper way of dealing with this. As far as I
can tell from your description of the patches, you'll end up with the
same mess again if you happen to have two disk arrays serving one
client. I would prefer a more generic method which uses NOTIFYCMD to let
users know that the disk array is going down.

> I'll get patches sorted out and post them to the list. If they get accepted 
> here then I'll send the necessary changes to the WinNut maintainers.

Please use unified diffs so that it is a little clearer to see what is
going on.

Kind regards, Arjen

More information about the Nut-upsdev mailing list