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On a Ubuntu 8.04 I have two interfaces eth3 and eth4:avahi.

eth3 is in my local network with
eth4:avahi has the ip

From this box I can ping successfully.

On a windows box in the same local network with ip I want also be able to reach To achieve this I used the following steps:

  1. On the windows machine I entered as gateway.
  2. On the Ubuntu I activated /proc/sys/net/ipv4/ip_forwarding

Now on the windows machine I can ping but not ping

What I am doing wrong?

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up vote 1 down vote accepted

Reason: don't know route to network.
1. Add route to network on
2. Use NAT on Ubuntu_8.04.

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Thanks. How do you do 1. and 2.? Especially as the 212-box is a OpenVZ-guest on the 211-host – user4514 Aug 1 '11 at 9:15
What is the default gateway of the 212 box? – Paul Aug 1 '11 at 13:02

I don't know what an OpenVZ-guest is, but if it is a host on the Internet then you will have to use network address translation (NAT) on your Ubuntu host because 192.168.x.y addresses are not routable beyond your local network.

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