Are your linux box running IPTABLES? If yes, disable it first, then tighten
it up step by step.

Ida Young
Support of ITShield firewall
http://www.itshield.com

"Martin Baumann" <mrbaumann@gmx.de> wrote in message
news:a6743618.0306240626.5f351ee8@posting.google.c om...
> Hi all,
>
> the following scenario:
>
> lan1: 192.168.1.0/24
> lan2: 10.200.30/24
> eth0 = 192.168.1.1/24
> eth1 = 10.200.3.254/24
>
> a dualhomed linux-box (debian-woody stable, custom kernel 2.4.20 from
> kernel.org) should route between the two networks. i activated
> ip_forwarding with 'echo 1 > /proc/sys/net/ip_forwarding' and the
> routing table looks like the following:
>
> Kernel IP routing table
> Destination Gateway Genmask Flags Metric Ref Use Iface
> 10.200.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
> 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
>
>
> i can ping both interfaces from the according lan and interestingly
> i'm able to ping 192.168.1.1 from a machine inside the 10.200.3.0-lan,
> but that's it. i cannot ping other machines in the 192.168.1.0 net
> from 10.200.3.x and vice versa it's the same.
>
> i would be glad about any hints what could be going on, since as far
> as i know there is nothing more to do except activating ip-forwarding
> for a linux box to act as a simple router between two lans. gated or
> routed is only neccessary for dynamic routing, correct me if i am
> wrong!
>
> greetings,
> martin