[Nut-upsdev] Question about hardware failures / FSD

João Luis Meloni Assirati jlmassir at gmail.com
Tue Sep 29 22:52:26 BST 2020

Hello Daniel!

On Tue, Sep 29, 2020 at 6:23 PM Daniel F. Dickinson
<cshore at thecshore.com> wrote:
> Hello joão,
> To get more responses you should plaintext email (standard for open source development mailing lists) instead of HTML mail.

I just can't believe that I was sending HTML e-mail. Thank you very
very much for bringing this to my attention. I hope it is ok now.

> >The UPS I am developing a driver to is able to report several flags for critical hardware conditions, like overheat, overload, inverter failure, output short etc. What should be the correct policy of operation >when such a condition occurs? I think that the an UPS in such a condition is not reliable and therefore a system shutdown should be called. However, the developer's manual and all other drivers I inspected >seem to call the FSD flag only when there is a shutdown already in progress (say, a countdown register is active).
> The decision about whether to do a forced shutdown is, I believe, considered a local administrator decision.  I would suggest that you should make these 'events' like low batter or communications failure, and let the admin choose what to do about the event.

I see. I think I understand it better now. The driver's job is to
inform hardware status. The decision of what to do with this status
concerns more to the clients (upsmon or other client talking to upsd).
This will simplify my code.

However, I think there should be some universal flag telling upsmon
that something really bad is going on. Maybe raising alarms, but as
far as I understand there are no standard alarm messages. Some drivers
use things like OVERHEAT, other use textual messages like "The UPS is
too hot!". Can you please send me some advise about this matter?

> >
> >So far none of my questions were answered, but I hope eventually someone will have some time to spend helping me.
> Regards,
> Daniel

Thank you,
João Luis.

More information about the Nut-upsdev mailing list