I have a strange problem.
I have ssh daemon running on my server (192.168.1.2, eth0).
Default gateway all traffic is 192.168.1.1 (my router).
Router has a public ip 18.104.22.168 and port 22222 is forwarding everything to my server (192.168.1.2) on port 22.
That is nothing special.
I just set port when I want to connect to my server from outside:
ssh -p22222 firstname.lastname@example.org
When I connect to a VPN server I get on tun0
device IP 10.0.2.3 (tun0). Default gateway is being changed to 10.0.2.1 and only connections to 192.168.1.0/24 are going through 192.168.1.1
That is absolutely OK because I want all connections to go through VPN.
This is where the problem begins:
When I now try to connect from outside (i.e. 22.214.171.124) to my server by using the above command connection is not being established. iptables log gave me the explanation:
1. incoming packets for server connection are coming through eth0
2. but outgoing packets from my server to 126.96.36.199 are going through VPN gateway (10.0.2.1, tun0) (because that is default gateway when VPN connection is active)
Any ideas how could I solve this? I could set one more route for IP 188.8.131.52 to force it to go through eth0 but 184.108.40.206 is a dynamic IP which I get on my 3G connection on my notebook.
I was thinking about prerouting/post outgoing packets on tun0 for port 22 to eth0 but I was not able to find anything for that in iptables. Is it even possible to solve it like that?
Could I maybe somehow add route on first incoming packet for this IP and delete it when the connection is gone?
Or is there some much elegant solution?