On Wed, Sep 05, 2001 at 04:21:11AM -0700, Carson Wilcox wrote:
> I'm trying to get PPP to work across a serial link
> (null modem), Linux to Linux and my head must have
> gotten thick yet again.
>
> I can ping 'localhost' on both boxes and have an entry
> in /etc/hosts but when I try to start pppd on either
> box I get an error that the IP is bad.
>
> The command I'm using for pppd is:
> pppd -detach crtscts lock <local IP>:<remote IP>
> /dev/ttyS0 3800 &
Carson...
Here is how I have pppd set up between two linux boxes over a null
modem line:
box 1 runs debian potato (stable) with kernel 2.4.6 (I had to upgrade
pppd to 2.4.0 - the one supplied with the distro didn't work right
with 2.4 kernels). box 1 is sort of an all-purpose router type-thing
where it can work as a modem dialout, cable modem firewall and ppp server.
box 2 runs debian testing (unstable) with kernel 2.4.8 and pppd 2.4.1
--
box 1 ('server'):
in /etc/inittab:
T0:23:respawn:/usr/sbin/pppd /dev/ttyS1 57600 -detach lock
noauth proxyarp debug crtscts 192.168.1.10:192.168.1.4
(that's all one line)
the debug bit can be very helpful....
the -detach is needed otherwise init will keep respawning pppd's
i use completely different ip's than the ip's on ethernet, to keep
from conflicting with other connections. on ethernet, there are
192.168.1.1-3, and ppp uses 4 and 10
on box 2 ('client'):
as root:
pppd /dev/ttyS0 57600 noauth nodefaultroute
the nodefaultroute bit keeps it from changing the default route on
my system to that of the ppp 'server', so my real internet still
goes on the ethernet link. sometimes I use defaultroute if the ethernet
is not up and my only link to the router will be the serial ppp link.
the noauth bit is for convienence, otherwise I'd have to make a
/etc/ppp/*-secrets file for security, but since it is a serial link
I'm not worried about it.
I emptied my /etc/ppp/options files to make sure that only the
command line options are in effect. so hopefullt this should work
for you. tcpdump -i ppp0 will be helpful, as will the debug options.
hth,
bill
This archive was generated by hypermail 2.1.3 : Fri Aug 01 2014 - 18:50:06 EDT