System: CentOS 7.
/etc/sysconfig/iptables is like this:
... -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p icmp -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -i gre1 -j ACCEPT # not working -A OUTPUT -o gre1 -j ACCEPT # not working -A INPUT -j REJECT --reject-with icmp-host-prohibited
If the last line exists, my GRE tunnel is not working, ping/everything does not work (although tcpdump captures ping packages at the other end) and if I remove the final line in the
iptables file, everything works.
What "command" should I specify to allow all traffic from gre1 but iptables is still enforcing rules on eth0?