Subject: building an embedded NetBSD
To: None <>
From: Paul Dokas <>
List: current-users
Date: 05/06/2003 14:00:54
I've aquired an old Lucent Brick 80 that's basically a 486 class PC with
CompactFlash instead of a disk drive and 4 Intel based NICs that I'd like
to get working as a firewall.

What I think is the best approach is to get a trimmed down version of
NetBSD onto the CF that is similar to the installation floppies.  Basically,
the CF would hold a kernel that mounts and populates a memory disk (md(4))
in the same sort of way that the installation floppies do.  However, I'm
having a little trouble figuring out exactly how to build such a thing.

I know that I have to build a kernel with something like this:

options         MEMORY_DISK_HOOKS
options         MEMORY_DISK_IS_ROOT     # force root on memory disk
options         MEMORY_DISK_SERVER=0    # no userspace memory disk support
options         MEMORY_DISK_ROOT_SIZE=4600      # size of memory disk, in blocks

but how to actually populate this space is beyond me.  I've dug through
/usr/src/distrib/, but it's like the maze in adventure (Twisty little
passages, all look the same...)  What happens in there to actually create
the boot floppies is not clear.  Can anyone please shed a little light on
how the i386 boot floppies are actually created?  I'd like to do something
similar, probably by hand, to get NetBSD onto this device.

Paul Dokas                                  
Don Juan Matus:  "an enigma wrapped in mystery wrapped in a tortilla."