Routing problems (2 network segments)

Hi!

I have changed the topology of my small LAN a little bit, because I
have bought a T-Sinus 111 (router+ADSL-modem+WLAN-AP) see sketch at
the buttom. Everything is running fine, but there is one problem: I
can't ping the router from the LAN-client - timeout. If I monitor the
eth0 interface traffic I can see outgoing ICMP echo requests but no
incomming traffic ;( It's the same if I try to request a internet page
- so the routing seems to be ok. btw, it's strange, that I can ping
the WLAN client without a problem - he is in the same network segment
as the router ;-/ Any hints for me ?

At the buttom you can see most of my relevant network configuration.

thanks in advance for your help

cu Erik

Internet
|
|
DSL
WLAN-AP-----------------Client A (Wireless)
Router 192.168.2.100
(T-Sinus 111)
192.168.2.2
|
|
|
| 192.168.2.1 (eth0) Server 192.168.1.1 (eth1)
+----------------------- Debian ------------------------- +
Linux |
Server |

Switch

|

|
Client 1

192.168.1.100

The routing table on the server looks like this:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref
Use Iface
192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
0.0.0.0 192.168.2.2 0.0.0.0 UG 0 0 0 eth0

IP-Forwarding is on!

# /etc/network/interfaces

auto lo eth0 eth1
iface lo inet loopback
iface eth0 inet static
address 192.168.2.1
netmask 255.255.255.0
network 192.168.2.0
broadcast 192.168.2.255
gateway 192.168.2.2

iface eth1 inet static
address 192.168.1.1
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.2.2


dhcpd.conf (DHCP listen on et0 und eth1)

[cut]
subnet 192.168.1.0 netmask 255.255.255.0 {
range 192.168.1.150 192.168.1.200;
option routers 192.168.1.1;
[cut - fixed IPs]
}

subnet 192.168.2.0 netmask 255.255.255.0 {
range 192.168.2.150 192.168.2.200;
option routers 192.168.2.1;
[cut - fixed IPs]
}

On Tue, 11 Nov 2003, Erik Schumacher <(E-Mail Removed)> wrote:
> Hi!
>
> I have changed the topology of my small LAN a little bit, because I
> have bought a T-Sinus 111 (router+ADSL-modem+WLAN-AP) see sketch at
> the buttom. Everything is running fine, but there is one problem: I
> can't ping the router from the LAN-client - timeout. If I monitor the
> eth0 interface traffic I can see outgoing ICMP echo requests but no
> incomming traffic ;( It's the same if I try to request a internet page
> - so the routing seems to be ok. btw, it's strange, that I can ping
> the WLAN client without a problem - he is in the same network segment
> as the router ;-/ Any hints for me ?
>
> At the buttom you can see most of my relevant network configuration.

Your router only knows the 192.168.2.0/24 subnet and nothing about
192.168.1.0/24 or how to route to it. The simplest solution would be to
masquerade your 192.168.1.0/24 as your 192.168.2.1 IP.

Otherwise you could possibly do something with smaller subnets within the
192.168.2.0/24 range along with proxy_arp, but too difficult to explain in
a few words. I do that where my wireless subnet is a 255.255.255.248
portion of my main 255.255.255.0 LAN.

> Internet
> |
> |
> DSL
> WLAN-AP-----------------Client A (Wireless)
> Router 192.168.2.100
> (T-Sinus 111)
> 192.168.2.2
> |
> |
> |
> | 192.168.2.1 (eth0) Server 192.168.1.1 (eth1)
> +----------------------- Debian ------------------------- +
> Linux |
> Server |
>
> Switch
>
>|
>
>|
> Client 1
>
> 192.168.1.100
(snip)
--
David Efflandt - All spam ignored http://www.de-srv.com/

(E-Mail Removed) (David Efflandt) schrieb:

>Your router only knows the 192.168.2.0/24 subnet and nothing about
>192.168.1.0/24 or how to route to it. The simplest solution would be to
>masquerade your 192.168.1.0/24 as your 192.168.2.1 IP.

With masquerading it works fine now - thanks for your hint.

cu Erik