From: jimj@miller.cs.uwm.edu (James Jegers)
Newsgroups: comp.unix.bsd
Subject: Slip Documentation
Date: 22 Jan 1993 00:03:55 GMT
Organization: University of Wisconsin - Milwaukee
Distribution: world
NNTP-Posting-Host: 129.89.9.13
Keywords: slip

   For all of you which are having problems with slip, I have
written some DOCS on various things.. Let me know if you have
any problems with it.


    The easy to understand instructions on how to use/setup SLIP.

  I will be using two names, the remote side and the local side.

  remote side = the machine connected to the network, the machine with
		the modem on answer, etc.
		For me it is enigma or 129.89.9.119

  local side  = Your machine at home, the modem which will be dialing.
		For me it is jimj   or 129.89.53.11

   
1. First to set up the modems.  Set them up at the highest baud rate at
   which you can.  Note: currently baud's above 9600 have a tendency
   to make 386bsd's serial port drivers puke, so you might want to test
   them at a lower rate.
   Make sure you have software flow control turned off, otherwise
   the modems will "eat" all of the control-s's and control-q's which
   get send across it.  (It took me a long time to figure why slip wasn't
   working!!! grr) Set it to hardware control, or possibly turn it off.

   Also you need to make the remote modem answer the incoming call, 
   See your modem manual for complete details, but for HAYES modems you
   set the number of rings it picks up at by

   ats0=4     ->  to set the ring count to 4,
		  set it to 0 if you don't' want the modem to pick up anymore.

   I also turn echo off so the modem is spitting back what getty sends
   to it.. I think it's  ate0 but can't remember for sure.

   You also need the slip driver compiled into your kernel, the default kernel
   has this in it's config file.  The line looks like

   pseudo-device   sl      2

   There has also been many fixes to the slip driver in the patchkit,
   Including this one which fixes a patch in the patchkit.

Article: 10918 of comp.unix.bsd
From: sommerfeld@apollo.hp.com (Bill Sommerfeld)
Subject: Re: [386bsd] SLIP is one way...

Part 2 of patch 19 appears to contain a bogus duplicate return:

***************
*** 623,629 ****
        sc = (struct sl_softc *)tp->t_sc;
        if (sc == NULL)
                return;
!       if (!(tp->t_state&TS_CARR_ON))  /* XXX */
                return;

        ++sc->sc_bytesrcvd;
--- 630,640 ----
        sc = (struct sl_softc *)tp->t_sc;
        if (sc == NULL)
                return;
!       if (c > 255 || !(tp->t_state&TS_CARR_ON)) {       /* XXX 30 Aug 92*/
!               sc->sc_flags |= SC_ERROR;
!               return;
!       }
!
                return;		<-****!!!!****

        ++sc->sc_bytesrcvd;

.. which turns slinput into a noop.
I just deleted that return from my kernel, rebuilt it, rebooted it,
and I'm now typing this message over a SLIP link..

-------REMOTE SIDE------

2. Create a login id which has sliplogin as a shell,
   I don't think it needs to be a root account, but I haven't tried it
   as a regular account yet...

   sjimj::0:10::0:0:James Jegers,786-3316,,:/rootjj:/usr/sbin/sliplogin

.  Modify the /etc/slip.hosts file to contain an entry which matches the
   username in the password file.   Note the order of local/remote
   address are reversed.
	     
   login  remote addr   local addr      netmask           
   sjimj  enigma        129.89.53.11    0xffffff00     normal 

3. Make sure you have the files /etc/slip.login and /etc/slip.logout
   in the /etc directory and that they are executable!, if they
   are not there, you can probably copy them from
   /usr/src/usr.sbin/sliplogin/slip.login

4. Modify your /etc/ttys file to contain an getty entry so you can login
   when you dial into the machine.  And make sure you turn the line
   "on", and rehup your machine,  kill -HUP 1 
   Note: there have been many patches to the com driver, and at least
   one version of the com driver makes your mouse get screwed up
   if you have getty running on the other com port.

   #  the std.9600 means ONLY 9600. use d9600 for 960,19200 switch
   com2    "/usr/libexec/getty std.2400"   dailup  on secure

-------LOCAL SIDE-------

5. Use kermit or tip to dial out of the modem.  Dial the number
   Of the other modem, when it connects login as the slipuser(sjimj)
   and it should say, "starting slip connection"

6. Then suspend your kermit/tip session, or if you have your modem setup
   to ignore DTR, you may quit your kermit/tip session.

7. Run ifconfig to setup the device.

   ifconfig sl0 inet localaddr remoteaddr netmask 0xffffff00 metric 1

     ifconfig sl0 inet 129.89.53.11 129.89.9.119 netmask 0xffffff00 metric 1

   ifconfig sl0 now shows    
     sl0: flags=11<UP,POINTOPOINT> metric 1
	     inet 129.89.53.11 --> 129.89.9.119 netmask ffffff00 

   netstat -r now shows
     enigma           129.89.53.11       UH          1        1  sl0

8. Run slattach to setup the connection.

   slattach /dev/com2 9600

     Note:  There is a new version of slattach out which support the 
     compressed packets which is called with,

   slattach -a -s 9600 /dev/com2

9. You should now be able to ping/telnet to the machine on the
   other side of the slip connection.

10.If you want to ping/connect to machine past the machine on the other
   side of the slip connection you need to set all the routing information
   on all of those other machine so that they know in order to get
   to your machine they must first go though the machine which you are
   connected to.
    
-----------------------------------------------------------------------------
PS. I'm not responsible for anything you do with this document or anything
    you wreck using it.  I just wrote the docs for to help the community.

     ______________________________________________________________
    /\               University of Wisconsin -- Milwaukee          \
    \_| Computing Services Division     Computer Science Department |
      |   jimj@csd4.csd.uwm.edu           jimj@miller.cs.uwm.edu    |
      |   jimj@convex.csd.uwm.edu                                   |
      |   __________________________________________________________|___
       \_/_____________________________________________________________/



Newsgroups: comp.unix.bsd