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I'm feeling a bit stupid because this seemingly simple task is completely stumping me.

I have 3 PCs: Client, Gateway and Server.

Client needs to connect via Gateway to Server.

Both PCs are connected to gateway via crossover cables.

Static IPs have been given to each interface.

ip :\24

Gateway eth4

Gateway eth1

Server eth0

Client can ping Gateway eth4 and eth1, Server can ping Gateway eth4 and eth1 but Client cannot ping Server.

Gateway can ping everything.

At first I thought I needed to insert static routes on Client and Server but this did not help and I now think that as they can ping the Gateway interface on the other network it is not necessary?

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More information on the nature of the gateway might be helpful. what kind of hardware/software (OS, etc.) is it? Do you have the interfaces bridged? – Dennis Williamson Feb 24 '11 at 0:14
up vote 2 down vote accepted

Have you turned on IP routing?

$ cat /proc/sys/net/ipv4/ip_forward 

If the output is '0', then you need to turn it on:

$ sudo sysctl -w net.ipv4.ip_forward=1

Change the setting in /etc/sysctl.conf to make it persistent.

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yep, it looks like the OP has not told the gateway OS to forward packages :-/ – DutchUncle Feb 24 '11 at 17:33

So client1 hits its gateway at 138.254 that goes to 138.1 back to itself?...

Client:eth1 ip :\24 *

Gateway eth4 ip\24
gateway *

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this was supposed to be a question, not answer...sorry new here. – egroeg Feb 24 '11 at 1:28
The big 'ask question' button up in the upper right is where to ask questions. – sysadmin1138 Feb 24 '11 at 3:05
thanks for the warm welcome ;) – egroeg Feb 24 '11 at 4:05

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