Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 30 Jan 1996 13:14:38 -0600 (CST)
From:      Joe Greco <jgreco@brasil.moneng.mei.com>
To:        terry@lambert.org (Terry Lambert)
Cc:        msmith@atrad.adelaide.edu.au, terry@lambert.org, hsu@clinet.fi, hm@altona.hamburg.com, freebsd-hackers@freebsd.org, brian@MediaCity.com
Subject:   Watchdog timers (was: Re: Multi-Port Async Cards)
Message-ID:  <199601301914.NAA05659@brasil.moneng.mei.com>
In-Reply-To: <199601300255.TAA05407@phaeton.artisoft.com> from "Terry Lambert" at Jan 29, 96 07:55:48 pm

next in thread | previous in thread | raw e-mail | index | archive | help
> > If you have a source for the $35 variant, I'd love to see it.  The only 
> > reference I managed to track down was for a $400 product, which unsurprisingly
> > failed to enthuse me.  Currently I install 8-port relay boards in a
> > nominated 'stable' system, and run lines from the motherboard reset pins
> > to the relays.  Crude, but _very_ effective.  (Until someone runs the 
> > 'cylon' program I use to test the cards 8)
> 
> One of the Europeans (Joerg?  Soren?) built a card.

Emerging Technologies has a pricey but (apparently) flexible watchdog card,
as I recall it was around $200.

I lost the Web page reference for this one:
ftp://ftp.mediacity.com/pub/brian/dvi-watchdog-1.5-freebsd.tar.gz
but it was posted on one of the lists in a discussion a while back by Brian
Litzinger.  Ooooo there it is, see his announcement of Wed, 18 Oct 1995 in
-hackers.  I haven't found a source for the BOARD itself.  Maybe Brian can
give us a hint where to look.

I've seen other generic PC watchdog/rebooters in magazines for an average
cost of about $100.

What I'd like:  a watchdog that didn't cost as much as a much more
sophisticated piece of equipment such as an Ethernet or SCSI controller.
A $35 variant is about right.  :-)  The parts are dirt cheap.

Ideally I'd like to see a watchdog driver that knows how to work with
FreeBSD.  Brian's work is workable but it would be much nicer if the
watchdog driver would automatically deal with the watchdog board in a
logical manner without having to putter with modifying system commands.
The way I envision it, the driver comes up, sets the timeout to something
big like 10 minutes, and that's initialization.  When the RC scripts start
running, it runs a user-level configuration utility before the fsck's, that
sets the board to reset in X minutes (i.e. if fsck's don't succeed).  In
rc.local, a user-level daemon gets kicked off, which sets the board to reset
in 5 minutes, and then proceeds to ping the board every minute.  I assume a 
device driver is notified when the system is going down, so when
halt/shutdown/whatever are called to bring the system down, the board is
reset by the devdriver back to the 10 minutes, and the system goes down.

This is (IMHO) conceptually clean.

I was thinking about tackling the problem myself by putting an 8751-class
microcontroller on a PC card and writing a quick'n'stupid bit of timer code
for the 8751 that would do all the dirty work (mainly because I would hate 
trying to wire all the digital logic for a traditional watchdog counter,
and I'm not familiar with any of the Maxim-type monolithic watchdog chips).
I don't have PC board facilities available to me and the prototyping cards
are expensive$$$$$.

... Joe

-------------------------------------------------------------------------------
Joe Greco - Systems Administrator			      jgreco@ns.sol.net
Solaria Public Access UNIX - Milwaukee, WI			   414/342-4847



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199601301914.NAA05659>