routing problem: my LAN clients can't ping outside
 

Hello everybody,

I want to install a linux computer as firewall for my network.

my network had until now the following caracteristics on an SUSE 7.2 distro:

internet gateway -----(eth1) linux router (eth0) ---------- lan
x.x.166.190 x.x.166.1 x.x.166.1 x.x.166.0

The routing table was looking like this:

Destination Gateway Genmask Interface

x.x.166.190 0.0.0.0 255.255.255.255 eth1
x.x.166.0 0.0.0.0 255.255.254.0 eth0
x.x.166.0 0.0.0.0 255.255.254.0 eth1
0.0.0.0 x.x.166.190 0.0.0.0 eth1


Now I want to configure the Linux box with SUSE 9.1, but i have problems with the routing.

The problem is, that I can ping from every computer in the internal LAN every other computer, and every interface of the linux box, but not the internet gateway. From the linux box I can ping everything: LAN clients and Internet gateway.

It seems that some instruction is missing which allows the 'bridging' of the two interfaces eth0 and eth1. Or perhaps it's only a small setting that I forgot.

IP_FORWARD is allready activated. The routing table looks like this:

Destination Gateway Genmask Interface

x.x.166.190 0.0.0.0 255.255.255.255 eth1
x.x.168.0 0.0.0.0 255.255.254.0 eth0
x.x.166.0 0.0.0.0 255.255.254.0 eth1
0.0.0.0 x.x.166.190 0.0.0.0 eth1

What would you sugest me to get that thing working.

Every help will be very apreciated.

C.

Hi there,
I think your ICMP packets need to be esplicitly let through
Check the link;
http://www.topology.org/linux/fwsuse.html#dingo.
Has a pretty comprehensive overview of a SUSE 9.1 setup, and for ICMP types check;
http://www.iana.org/assignments/icmp-parameters