Date: Mon, 31 Jan 2005 10:50:55 -0500 (EST) From: Jerry McAllister <jerrymc@clunix.cl.msu.edu> To: billy@nlcc.us (Billy Newsom) Cc: freebsd-questions@freebsd.org Subject: Re: How do I do a COLD Reboot on FreeBSD? Message-ID: <200501311550.j0VFot428451@clunix.cl.msu.edu> In-Reply-To: <41FE50F5.9000705@nlcc.us> from "Billy Newsom" at Jan 31, 2005 09:38:29 AM
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> > Jerry McAllister wrote: > >>I need to do a cold restart. I've looked through a lot of docs, and I > >>can't > >>seem to find this out. The computer I am working with seems to no longer > >>enjoy a warm reboot (like "shutdown -r now" or "reboot") but I'm pretty > >>sure > >>it will do cold reboots fine. Is there a port, or is the shutdown command > >>hackable for this, or what? > >> > >>I remember many computers in bygone years which had this problem. It was > >>pretty common back in the 90's it seems like. Computers would reboot and > >>act > >>weird using CTRL-ALT-DELETE, but work fine when powered off and on. > > > > > > FreeBSD is pretty good about doing a very clean reboot as far as the OS > > is concerned. But, it is possible that some devices don't clean up well > > in ways that are out of FreeBSD control. So, a "cold boot" can be a > > good idea in some circumstances. > > > > To do this, do a 'shutdown -h now' or a 'shutdown -p now' if your > > hardware supports the -p and you have it set up. Choose your own > > time of delay for 'now' if you have other people on the machine. > > > > If you did the '-h' or the '-p' didn't turn off the power, then > > at the "press any key to reboot" prompt, turn off the power. > > Then, unplug the power source and let it set for a few minutes to let > > any charge dissipate. This can be important because the capacitance > > in some of the devices including the power supply can provide just > > enough charge to keep them from reloading if that is their inclination > > and you lose the effect you are looking for. You should also unplug > > the network connection and any external devices that have their own > > power supply. > I know that this is all very good advice and information from the shutdown > man page and good stuff about the nature of capacitors, but all of this is > known to myself and unfortunately not useful... The shutdown -p does > essentially a different thing (and one time it caused the freeze problem to > disappear.) but this also does not work. I don't want to shut the computer > off, anyway, I want it to reboot back to FreeBSD remotely if need be. > > And so far, the halt command (or its shutdown -h equivalent) is not what I > want, either. If I press a key to reboot, I get the same issue anyway. > There's a remote possibility that the halt code is causing the freeze up, > because FreeBSD 4.7 did not have this problem. I'm not confident whether the > machine broke or the new 5.3 code broke, so I won't speculate which. I just > need the reboot code. > > ... > > > After a sufficient time drain capacitance - I usually go to the bathroom > > or go get something to drink to kill a few minutes - , then just plug > > it all back in. Plug in the network cable and any external devices first > > and then the power cord and turn it on and let it boot. > > It's not the capacitors, but perhaps some strange bug in the BIOS or > something, I guess. The issue that I'm highlighting is that when a floppy > program does a cold reset of this machine, the system (re)boots normally. Well, I guess I completely do not understand what you are asking. >From anything I can get from what you write here, its behavior is normal and expected. What is the problem and what are you trying to fix or to get it to do? A cold boot - which is what you ask about in your original post - is a boot all the way up from a powered off machine as far as I know. So, all I did was explain how to get what you asked for in the post. Another small guess - are you looking for 'shutdown -r now' by any chance? If you want something else, you will need to explain that. Who knows if anyone will know what to do about that - at least not until you reveal what it is. ////jerry > > As a side note, I have run this machine through the ringer trying to discover > any hardware errors. The memory is now EDO ECC (it had been something else) > and the problem persists. I have run diagnostics, memtest86, etc. Futile. > The cold reset code exists somewhere. Anybody? > > Billy > > > > Voila, you have gone from warm to cold to warm again. > > > > ////jerry > > > > > >>The computer I've got actually fails a memory test during the warm reboot. > >>This freezes it. I have to power cycle the machine. And then, the computer > >>performs a warm restart, bypassing its memory checks! One more power cycle > >>laster, it will boot normally. If I don't do this last reboot, the FreeBSD > >>boot loader or the beginning of the kernel boot crashes very early. It's > >>stable otherwise on a cold reboot. > >> > >>Thanks, > >>Billy > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" >
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