>From: matthew green <mrg@eterna.com.au>
>
>i have this problem repeatably with my netboot machines.  it happens
>if i do any serious work on a filesystem, not just /var or /usr, but
>any of my 'user' filesystems as well... (ie, if i use the machine to
>build, say src/libexec, it will fail to unmount either /var or the
>filesystem /usr/src is really on, but a freshly rebooted machine can
>reboot cleanly, no problem).

I second that.  My diskless i386 machine has a tendency to drop into
the kernel debugger if I'm rebooting it "when it has been up for a
while".  I wasn't able to reliably reproduce the problem, and I
haven't yet bothered to learn how to use the kernel debugger, so I
haven't been inclined to send in a PR (since I can't really provide
any coherent information about what's going on).

--
entropy -- it's not just a good idea, it's the second law.

This message may refer to a product containing software developed by
Christopher G. Demetriou for the NetBSD Project.