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Date: Mon, 21 Jul 1997 03:24:41 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199707201724.DAA11292@godzilla.zeta.org.au>
To: ahd@kew.com, current@FreeBSD.ORG
Subject: Re: current-digest V3 #104
Cc: bde@zeta.org.au
Sender: owner-freebsd-current@FreeBSD.ORG
X-Loop: FreeBSD.org
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>Second, and more importantly, if I have a urgent need to switch to a
>serial console and I don't have time to regen or extensively reconfigure
>the kernel, I don't want to be blocked by the kernel refusing to use a
>reasonable default.   (One of my systems doesn't have a normally have
>monitor -- blindly feeding a boot -h is doable, a kernel reconfig is
>_not_.)

Actually, it is: boot with -hc, then wait for userconfig to start,
then type `flags sio0 0x10<return>q<return>' and reboot (switching
of consoles in userconfig currently only works for switching between
syscons and pcvt).  Or if the system boots far enough for you to login
from somewhere, put this in /kernel.config:

	printf "USERCONFIG\n"flags sio0 0x10\nq\n" >/kernel.config

(or edit /kernel/config to preserve the existing configuration) and
reboot.  Or if you have a clue, put this in /kernel[.new].config
before booting the new kernel, or configure the new kernel before
using it.

Bruce