Date: Mon, 15 Mar 1999 16:13:03 -0500 (EST) From: Thomas David Rivers <rivers@dignus.com> To: dillon@apollo.backplane.com, ken@plutotech.com Cc: hackers@FreeBSD.ORG, smp@csn.net Subject: Re: power-off without halt Message-ID: <199903152113.QAA50381@lakes.dignus.com> In-Reply-To: <199903151941.MAA20523@panzer.plutotech.com>
next in thread | previous in thread | raw e-mail | index | archive | help
> > Matthew Dillon wrote... > > :Hi, > > : > > : We are looking at using FreeBSD as an "embedded OS" inside a line > > :of instruments we are building. I think I have a handle on all the > > :issues except how to cleanly handle shutdown where there is no > > :console, and thus no way to send a 'halt' command. The requirement > > :is that the user can merely turn off the power, nothing more required. > > : > > : I can modify the disk setup, kernel/util code as needed, I just need some > > :idea for a workable solution. Has anyone delt with this problem before? > > : > > :-- > > :Steve Passe | powered by > > :smp@csn.net | Symmetric MultiProcessor FreeBSD > > > > Well, physically speaking you can't power off a machine that may > > be writing to its disk. If it is in the middle of a write, you > > *will* lose sectors to hard errors. > > > > So, typically, the best way to deal with this sort of situation is > > to mount the disk read-only and never write to it. Or to not have a > > disk at all. Or to use a pcmcia type flash disk. > > SGI boxes have a neat feature (or at least they did when I did IRIX work a > few years ago). They have a "soft" power off switch. You hit the switch, > and it safely shuts down the machine. > I believe you can make pressing <cntrl>-<alt>-<delete> on the console do the same thing (or close to it) on FreeBSD. It's not a "switch" but it's close... - Dave Rivers - To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199903152113.QAA50381>