Re: Routing between 2 NICs

David Schwartz wrote:
> On Feb 9, 6:35 am, S Vertigan <steve-n...@vertigan.wattle.id.au>
> wrote:
>
>> I have a fedora server with eth0 on a 178.18.10.0/24 local network with
>> an internet gateway of 172.18.10.254 and eth1 is on another local network
>> of 192.168.242.0/24. All traffic from the second network is NAT'd and
>> the PCs have 192.168.242.110 (eth1's IP addr) as their gateway. These
>> machines can ping addresses on the internet but they can't reach any IP's
>> on eth0's network except for eth0 (172.18.10.2) itself.
>
> Does their gateway know how to reach those machines?
>
>> I assume there's a tweak with route would fix this but I've tried
>> route add -net 172.18.10.0 eth0
>> but that route was already in there. I only need one host (172.18.10.1)
>> to be reachable from the other network so maybe something like
>> route add -host 172.18.10.1 gw 192.168.242.110
>> except that would surely be wrong from the servers perspective. Any ideas?
>
> Troubleshoot. "I can't ping" doesn't narrow down the problem. Do the
> ping packets go out? What machine are they addressed to? Do they get
> to the destination machine? Where does the destination machine send
> its ping replies? Does that machine know how to reach the original
> source? And so on.
>
> DS


You have to tweak the NAT rules so that the destination to
172.18.10.0/24 is excepted from the NAT.

(I hope that the 178.18.10.0/24 address above is a typo).

--

Tauno Voipio