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I'm using a 3G modem whilst o2 tranfer over adsl. trouble is no websites load but I can resolve domains. I enabled masquerade on the PPP0 ( modem) interface. added the server as default route for all workstations.

iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE

net.ipv4.ip_forward = 1″ to /etc/sysctl.conf


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up vote 0 down vote accepted

Can you get to the remote system's tcp port 80?

#any of these would work.
telnet 80
echo > /dev/tcp/
nc 80

What does your iptables filter table look like?

iptables -L

Have you tried purging your iptables filter?

iptables -P INPUT ACCEPT
iptables -F INPUT
iptables -F OUTPUT
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I only have one rule thats listed when I execute iptables -L and thats's ACCEPT all -- anywhere anywhere. It's to allow connection from the rest of my lan into the server. My server has no monitor so I'm using ssh. When I was downloading using wget it couldn't connect. I also can't ping external ip's. But it works fine on the server. – ageis23 Sep 19 '10 at 9:20
I'm using my adsl router to issue ip's to the workstations, does this matter? It does have nat disabled so it should be a standard router. At least that's what the manual said. The chains are flushed automatically within the startup scripts. I'm also found some errors in the /var/log/messages file. My kernel doesn't support ppp filtering and pppd can't determine remote ip. – ageis23 Sep 19 '10 at 17:14
Then you might want to set some routs and see if those will work. – Kevin M Sep 20 '10 at 14:11
yeah sorry I gathered that. It wasn't clear on the tutorial. I was using ipmasq but by default it blocked everything and so I couldn't connect to my server. I removed all the rules to isolate which rules are blocking ssh. Also for some reason the ip forward wasn't sticking as well despite I added it sysconfig. – ageis23 Sep 20 '10 at 17:39

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