I'm having an issue with iptables impeding traffic from my openvpn (tun interface) clients. Before i go into details, I am positive that my routing (both push from openvpn and return from router) is set up properly, because everything works when i disable iptables completely. With this iptable enabled on the openvpn machine, i cannot get from the openvpn subnet to the rest of the lan.
I'm having trouble running iptables using RHEL 6.3.
iptables -A INPUT -p tcp --dport 1234 -j DROP
iptables v1.4.7: can't initialize iptables table `filter': Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
Heres my version of RHEL.
Red Hat Enterprise Linux Server release 6.3 (Santiago)
On Fedora 12 each reboot seem to reset my custom iptables rules I have manually added to /etc/sysconfig/iptables. My change are in /etc/sysconfig/iptables.old so obviously some process is removing them.
Any idea what this is? Any suggestions appreciated.