firewall?

hadimotamedi · 07-18-2011, 01:04 AM

Dear All
I have put my windows machine behind my centos firewall server with
just one NIC. At now, the windows machine can ping 192.9.9.3 but
cannot resolve valid url (like www.google.com). I have set DNS for it
as well. Can you please let me know what is the missing step?
Thank you

MS3FGX · 07-18-2011, 02:04 PM

How did you configure the firewall machine? It sounds like your firewall rules might be overly strict, and you are blocking DNS traffic.

Can you post the output of "iptables -L"?

hadimotamedi · 07-18-2011, 11:13 PM

Please find attached the required log.

hadimotamedi · 07-18-2011, 11:37 PM

I have set my centos 5.6 firewall as the following :
- Its eth0 @192.168.10.114
- Its eth0:1 @172.18.128.1
- Activate ip forwarding in /etc/sysctl.conf
'net.ipv4.ip_forward=1'
- Run 'sysctl -p' to reload settings
- Run the following command to share internet
'iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE'
- Set windows machine ip @172.18.209.1
- Set windows machine default gw @172.18.128.1
- Set windows machine DNS