UUCP over ethernet: It can be done!

[oacis.dnet!navoceano at turner-joy.noarl.navy.mil]

There have been several inquiries on this newsgroup re. running UUCP over
ethernet, or more exactly, over TCP/IP. I recently found myself needing
this capability and found a complex kluge which, none the less, seems to
work. 

The problem arrose when we attached our Sun 3/280 to a ethernet with
several Intergraph workstations and couldn't exchange mail with them. It
seems that the Intergraphs have several TCI/IP services (ftp, telnet,
rlogin, etc) but no SMTP.  In fact, for mail it seems they run UUCP over
an XNS link (another case of the truth being stranger than fiction)

After much hacking arround, we found a solution that would make Rube
Goldberg green with envy. Assume machines Sunny and Igraph:

1. Find two unused async. ports on Sunny, say /dev/tty0d and /dev/tty0e,
   and connect them together with a null modem cable.
2. Modify /etc/ttytab so that one port (e.g. tty0e) is a standard 9600
   baud login and the other is off.
3. Link /dev/cua0d to /dev/tty0d and change the owner to UUCP.
4. Add a line to Sunny's /etc/passwd file like:
   Ukluge::5:5:UUCP Kluge:/usr/spool/uucp/Ukluge:/bin/csh
5. Create Ukluge's home directory. Create .cshrc with:
   /usr/ucb/rlogin igraph -L -l nuucp
   logout
   <<The -L option is important.>> Be sure to chown these
     files to uucp. Nuucp is Intergraph's uucp login account.
     Use the appropriate account name for your system.>>
6. Add tty0d and cua0d in the L-devices file.
7. Add a line like this to Sunny's L.sys file:
   igraph Any,0 tty0d 9600 tty0d login:-EOT-login: Ukluge
8. Add igraph to the uucp.hr or uucp.day script.
9. Make sure igraph is setup for passive receive of Sunny's UUCP calls.

If this is set up right, when uucico on Sunny wants to contact Igraph it
will initiate a call out on tty0d. Without knowing what is going on,
uucico will log back onto Sunny's port tty0e as Ukluge. Ukluge's .cshrc
script will run rlogin to Igraph where it logs in as nuucp and runs the
other half of uucico.  As soon as uucico finishes, the rlogin is dropped
and Ukluge is logged out.

Notes:

1. It is probably not necessary to set up Ukluge with the same user and
   group numbers as uucp, but it was reasonable and convenient.  
2. There is probably a way to do this without tying up two async ports
   (e.g. pseudo ttys or pipes). If someone can think of a way to do this,
   please let me know. 
3. If your system blows up don't call me.

Don Newcomb
Naval Oceanographic Office
Stennis Space Center, MS
(601) 688-5998
navoceano at oacis.span.nasa.gov
navoceano%oacis.dnet at turner-joy.noarl.navy.mil