Setting up PC as router, eth1 problem talking to modem

NeXuS_2006 · 01-15-2005, 04:46 PM

Ok, heres the deal. I'v got Slack 9.1 installed (no Xwindows due to system's age), there are two NICs in (trying to setup the system as a router), and both seem to be working fine (not 100% sure), but the driver modules are loaded and running correctly anyhow. At this point I"m only worried about getting the PC to talk with my motorola cable modem, but it is having trouble getting an IP addy. I cannot ping my modem or any other system except loopback. In ifconfig, there is no IP ady for the ethernet card where it should be, it just says "UP BROADCAST NOTRAILERS RUNNING MULTICAST" Any help for me?

comprookie2000 · 01-15-2005, 09:40 PM

Is eth1 the card that is connected to the modem,do you use dhcp or static?
Here is how I did it,works good.
http://www.gentoo.org/doc/en/home-router-howto.xml

NeXuS_2006 · 01-16-2005, 10:34 AM

Yes, eth1 is connected to the modem, I am not worried about eth0 just yet, I just want this connected to the net first. We have a dynamic IP addy, in response to your question. Thanks for the link too, I'm reading it now, and it looks helpful.

mangolicious · 01-16-2005, 12:15 PM

try this:
this assumes eth0 is connected to lan and eth1 is connected to the modem. this also assumes it's not an external or internal dialup modem and that it's an adsl modem that uses PPPoE.

Code:

ifconfig eth0 192.168.1.1 netmask 255.255.255.0
ifconfig eth1 up
adsl-setup
*fill in stuff. don't hit "masquerading firewall" you will do that yourself.*
adsl-start
iptables -t nat -A postrouting -o ppp0 -j MASQUERADE
iptables -P INPUT DROP
iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -i eth0 -j ACCEPT
iptables -A INPUT -i ppp0 -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p tcp ! --tcp-option 2 -j REJECT --reject-with tcp-reset

if it's a dialup modem, then I have no clue...

mangolicious · 01-16-2005, 12:16 PM

oh wait a cable modem... hmmmm in that case, all I said with the ifconfig commands apply but the rest doesn't

michaelk · 01-16-2005, 02:36 PM

Have you tried configuring the network via
http://www.slackware.com/config/network.php
Configure eth1 for DHCP.

NeXuS_2006 · 01-17-2005, 01:23 PM

Thanks for all the replies, this gives me a lot of things to try. I'll let you guys know how it goes.