I need to install NetBSD on a machine with only a serial line for
retrieving the media.  I note that slattach and the sl pseudo-device
is in the INSTALL kernel, and presume that this means I can magically
use slip for an ftp install.  Although I am very familiar with pppd
for "normal" use, I've never used slip at all.  Hence, I have a few
questions.

First, is it even possible to configure the slip interface and use it
for an ftp install?

Second, I notice that sysinst strips away all potential interfaces
after the lo0 entry (src/distrib/utils/sysinst/net.c:159), so that
sysinst won't present sl0 as an option in its list of network
interfaces.  I removed that "feature" of sysinst, so that it will
present the entire list of interfaces.  I can select sl0 as an
interface, and the rest of the net configuration code (up to the ping
test which is as far as I can go without a real slip connection) seems
to work.  

  - Is this "feature" just to clean up the list for "normal" installs?

  - Is there a problem with proceeding with my modified sysinst and
    trying to get the sl0 device configured properly?

Third, it seems like a reasonable way to proceed with a slip
installation is the following:

  - boot install media with modified sysinst
  - exit sysinst
  - have modem dial slip server somehow (suggestions?)
  - slattach [options?] tty00
  - ifconfig sl0 inet local_address remote_address [more options?]
  - rerun sysinst program
  - setup network as always, but choosing sl0 as network interface
  - proceed with normal install

Fourth, if the above seems reasonable, I could use tips on the points
noted with question marks.

Finally, are there any shortcuts for setting up a slip server?  I
presume I need a login account with sliplogin as the shell.  The man
page for sliplogin seems fairly straightforward, but I would
appreciate any examples or suggestions.

Thanks for your help.

Cheers,
Brook