had a problem with the / partition getting full (105%) on a fileserver 
here and then rebooted it. after rebooting the "ERR M" line came up 
immediately after the "drive 0 partition 3" message that is normally 
followed by the boot prompt. this is an amd64 4.1-release machine and i 
can't account for this behavior aside from the overfull state of the / 
partition during shutdown.

so i booted off a USB drive (i386), mounted / from the other disk and 
cleared off the stuff that had eaten all the space. rebooted and got the 
ERR M again, so apparently something became hosed from the first time it 
was shutdown with an overfull /.

got an amd64 install onto the USB drive so i could attempt booting /bsd 
from the "hosed" drive. at the boot prompt did a "boot hd1a:/bsd" and 
the machine is running, albeit using a USB drive to boot the kernel from 
hd1.

have gotten the ERR M message before and recognize it indicates a bad 
magic number but am clueless as to how to fix it. clues appreciated 
here. find a link to the dmesg below.

cheers,
jake

dmesg - http://marc.info/?l=openbsd-misc&m=118141026830100&w=2

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