Hi eveyone,

I have recently installed Shorewall on Red Hat EL AS4 VPS to help me configure firewall/iptables.

After the installation and configuration of Shorewall whenever I start or restart Shorewall I get the following error: Can anyone help me understand what this error means and how do I reolve this issue?

Creating action chain Drop
iptables: Invalid argument
Error: Command "/sbin/iptables -A Drop -p tcp -j dropNotSyn" Failed
Processing /etc/shorewall/stop .....
IP Forwarding Enabled
Processing /etc/shorewall/stopped ...
/sbin/shorewall: line 774: 7734 Terminated $SHOREWALL_SHELL ${VARDIR}/.restart $debugging resart

Many thanks in advance for your help.