Puzzle involving serial console and ...??!?

[David Wolfskill]

I may be going mad -- that's likely the simplest explanation, and
Occam's Razor would thus indicate that this hypothesis should be
accorded a degree of plausibility, at least.

As described in <http://www.catwhisker.org/~david/FreeBSD/upgrade.html>,
I have my own quirky ways of upgrading FreeBSD systems, the basics
of which remain fundamentally unchanged for the last dozen years
(well, a few more than that, but...).  In turn, much of that approach
was borrowed from one of my pre-FreeBSD experiences in an IBM
mainframe environment (as a "systems programmer").

What's causing me to question my tenuous grasp of reality is this:
Referencing the above-cited Web page, my build machine ("freebeast")
normally runs headless, and I use a cable to connect its serial
port to the serial port of one of my other machines ("albert").

By doing so, I have a working serial console (once the FreeBSD
loader gains control from the BIOS, at least)... half the time.

I have determined that whether or not I have a functioning serial
console for freebeast depends on whether I boot albert from slice
1 or slice 2:  if from slice 1, it doesn't work; if from slice 2,
it does.

Even when the contents of the 2 slices are functionally equivalent
(that is, the file systems of the 2 slices are as "the same" as a
"dump 0Lf | restore" pipeline can make them, except for a deliberate
difference in the contents of /etc/fstab (as the root and /usr file
systems are on different slices in the two cases)).

I use tip(1) on albert to access the serial port (as I have since
1998); I leave the speed at the default of 9600 because it has --
save for this case -- always worked for me in the past.

Does anyone have any suggestions for figuring out what is really
going on here?  While I can't just reboot "albert," I have another
(similar) machine ("pogo") that I use for testing stuff that I plan
to do to albert, and I could easily connect teh serial cable to
pogo instead of albert and tinker with that.

Thanks.  I'm on the list, so list replies need not Cc: me.

Peace,
david
-- 
David H. Wolfskill				david at catwhisker.org
Those who would murder in the name of God or prophet are blasphemous cowards.

See http://www.catwhisker.org/~david/publickey.gpg for my public key.
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