I'm having some problems with firewall rules and would like the help of you guys.
I added a VPN connection (StrongSwan), but I can not access the network from the other end.
when I run the firewall script (iptables), the script flushes the rules (filter and nat) and adds the new rules. While the script rules are not added (policy: accept) I can access the other end of the VPN, but when the nat table rules are added, I lose the communication.
Yes, I know there must be an error in the nat rules, but I can not figure out exactly which rule(s) is(are) causing that impact.
I tried to use iptables TRACE, but I have a lot of rules applied and I can not understand the results and I can not locate exactly what the problem is.
And now the weirdest part (I think): I have another VPN connection (another network destination) configured on the same machine, with exactly the same rules and do not have this problem.
Can any of the experts give me an idea of how I can try do the troubleshooting or know how I can try to solve this problem? I'm lost!
Thanks in advance!