Simple question, difficult solution. I can’t work it out. I have a server at home with a site-to-site VPN to a server in the cloud. The server in the cloud has a public IP.

I want people to access server in the cloud and it should forward traffic through the VPN. I have tried this and it works. I’ve tried with nginx streams, frp and also HAProxy. They all work, but, in the server at home logs I can only see that people are connecting from the site-to-site VPN, not their actual source IP.

Is there any solution (program/Docker image) that will take a port, forward it to another host (or maybe another program listening on the host) that then modifies the traffic to contain the real source IP. The whole idea is that in the server logs I want to see people’s real IP addresses, not the server in the cloud private VPN IP.

  • @nickshanksOP
    link
    English
    01 year ago

    Okay, can we go back to those iptables commands?

    iptables -t nat -A PREROUTING -d {VPS_PUBLIC_IP}/32 -p tcp -m tcp --dport {PORT} -j DNAT --to-destination {VPN_CLIENT_ADDRESS}
    iptables -t nat -A POSTROUTING -s {VPN_SUBNET}/24 -o eth0 -j MASQUERADE
    

    Just to confirm, is the -o eth0 in the second command essentially the interface where all the traffic is coming in? I’ve setup a quick Wireguard VPN with Docker, setup the client so that it routes ALL traffic through the VPN. Doing something like curl ifconfig.me now shows the public IP of the VPS… this is good. But it seems like the iptables command aren’t working for me.

    • Admiral Patrick
      link
      fedilink
      English
      21 year ago

      Just to confirm, is the -o eth0 in the second command essentially the interface where all the traffic is coming in?

      That is the interface the masqueraded traffic should exit.