I'll toss in a little experience here (I have a serial link and a subnet
under a dynamic ip address).

First for the serial link (netbsd to macos) I put the ppp "server" in a
getty line for the modem port (tty01) 

tty01 "/usr/sbin/pppd /dev/tty01 57600 -detach" unknown on

then I used the /etc/ppp/options.tty01 file to setup the rest of the
connection.

lock # this is in the global options file
local
passive
persist
#silent # silent won't work with the macos ppp afaict
noipdefault
-defaultroute
10.1.2.0:10.1.2.1  #server address:client address
#auth	#using pap to authenticate the client (this is optional)
#name xavier #set the name of the server for pap 
 
Now about my little subnet and dns. Here is what I did. I set the
nameserver to be authoritative for my subnet and just cache for the rest
of the internet. I put the nameserver on my gateway and pointed the
internal machines to the gateway. 

Anyway this is what I did and it works for me. YMMV.

Later. 


On Sat, 27 Dec 1997, Bill Studenmund wrote:

> > 	1) Is there any sort of FAQ o setting up IPNAT? I'm trying to use
> > some of the scripts I've seen in various posts to the list, but none have
> > worked for me thus far. Here is my setup:
> > 
> > 	hobbes @ 10.0.0.3 # IIci running NetBSD
> > 		broadcast 255.255.255.10
> 
> Why the non-standard broadcast address? It should be 10.0.0.255 by
> default, given your netmask.
> 
> > 	brahms @ 10.0.0.1 # Q630 generally running MacOS (no CS ethernet
> > 			  # yet under NetBSD 
> > 	yoda   @ 10.0.0.2 # PB540c (no FPU, and LC040, so no NetBSD 8-()
> > 	newton @ 10.0.0.4 # IIcx running MacOS (video card and ethernet
> > 			  # card conflicts, so can't ifconfig.... I'll
> > 			  # send some info on it later to see if someone
> > 			  # can help fix)
> > 
> > 	* all have a 255.255.255.0 netmask
> > 
> > 	Hobbes has the PPP connection to the Internet, and I want to route
> > those packets to at least Brahms and Yoda so I can use Netscape through
> > Hobbes as a gateway. So far.... no luck. It MAY be that I need to figure
> > out the domain name stuff. Right now, Hobbes is my internal DNS, and it
> > also uses my ISP's DNS. What would be a good way to set up the TCP/IP
> > settings on my MacOS machines.... use Hobbes as a primary DNS and my ISP
> > as secondary? or vice versa?
> > 	
> > 	Right now, here's my nat-up script (called from /etc/ppp/ppp-up
> > after I get my IP address from my ISP.
> > 
> > #!/bin/sh
> > #
> > # nat-up - setup the nat with ppp
> > #
> > 
> > address=`ifconfig ppp0 | tail -n 1 | awk '{print $2}'`
> 
> Why do this? One of the parameters passed to the ip-up script IS
> the local address of the ppp link. From man pppd:
> 
>        /etc/ppp/ip-up
>               A program or script which is executed when the link
>               is available for sending and receiving  IP  packets
>               (that  is,  IPCP has come up).  It is executed with
>               the parameters
> 
>               interface-name  tty-device  speed  local-IP-address
>               remote-IP-address ipparam
> 
>               and  with  its  standard  input,  output  and error
>               streams redirected to /dev/null.
> 
>               This program or script is executed  with  the  real
>               and  effective  user-IDs  set  to root.  This is so
>               that it can be used to manipulate routes, run priv-
>               ileged  daemons  (e.g.  sendmail), etc.  Be careful
>               that  the  contents  of  the   /etc/ppp/ip-up   and
>               /etc/ppp/ip-down  scripts  do  not  compromise your
>               system's security.
> 
>               This program or script is executed  with  an  empty
>               environment,  so  you must either specify a PATH or
>               use full pathnames.
> 
> 
> 
> > echo Current IP address is $address
> > echo Cleaning out IPNAT
> > ipnat -F
> > ipnat -C
> > ipf -E
> > echo Setting up IPNAT for IP address $address
> > echo "map ppp0 10.0.0.3/24 -> $address/32 portmap tcp/udp 10000:65000" |
> > ipnat -f -
> > # the above is one line
> > echo "map ppp0 10.0.0.3/24 -> $address/32" | ipnat -f -
> > 
> > --------
> > 	and my nat-down (called from /etc/ppp/ppp-down)
> > 
> > #!/bin/sh
> > #
> > # nat-down - bring down the nat
> > #
> > 
> > ipf -D
> > ipnat -C
> > 
> > -------------
> > 
> > 	Do I just need to adjust the IP numbers to reflect my system? Or
> > is there something else going on? I've tried using 10.0.0.3 and 10.0.0.0
> > for the IP/netmask pair in the map ppp0, but neither has worked. I've
> > looked through the ipf ipnat and ipnat.conf man pages and they didn't seem
> > to help my understanding much...
> 
> I haven't tried this yet. I probably should just to see how it goes. :-)
> 
> > 	2) What would be a good way to set up a serial connection between
> > 2 NetBSD machines? I can't use ethernet between Hobbes and Brahms, but I
> > could at least use a SLIP/PPP connection between the two. I read something
> > about setting it up recently, but I've misplaced all of my old list mails
> > 8-( Anyone care to recap? ;-) I've not had any luck so far.... 8-(
> 
> Get a printer cable, and use it to hook the two computers together. Disable
> getty on both machines. Edit /etc/hosts on each one to assign an IP
> address to Hobbes-ppp and Brahms-ppp. Either 10.1.0.{2,3} or something around
> 172.16.0.X. Basically another "internal" pair of IP addresses, which AREN'T
> in the netmask of the ethernet.
> 
> Then on one (say Hobes):
> 
> pppd tty0X 38400 cdtrcts local passive Hobes-ppp:brahms-ppp
> 
> and on the other:
> 
> pppd tty0Y 38400 cdtrcts local passive
> 
> That should do it. They've changed the man page since I did this last, so my
> quick example's gone. :-(
> 
> Take care,
> 
> Bill
> 

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