Docker – Access to service in Docker container connected to VPN

dockernetworkingopenvpnvpn

I set up a Linux server (VirtualBox VM for now)

In that server I run a Docker container containing two things:

  • An app with web interface on certain port
  • Open VPN Client

I can access that app (from my host machine, since Linux is VM guest) and everything works fine until I connect VPN.

VPN works – traffic goes through it but I can't connect to my app anymore (ERR_CONNECTION_TIMED_OUT).

So my goal is to:

  • Have a server in Docker container where all the traffic goes through VPN
  • Be able to access that server/container in my local network (as I do now when VPN is not connected)

How can I achieve it?

This is how my .ovpn file looks like

client
auth-user-pass
ping 5
dev tun
resolv-retry infinite
nobind
persist-key
persist-tun
ns-cert-type server
verb 3
route-metric 1
proto udp
ping-exit 30
cipher AES-256-CBC

// cetrificate here

remote <remote-host-ip>

Best Answer

Have you tried creating a routing inside the docker?

Try adding these via command line:

ip rule add from X.X.X.X table 128
ip route add table 128 to y.y.y.0/24 dev eth0
ip route add table 128 default via Z.Z.Z.Z

Where: X.X.X.X is the LAN address of the docker

Y.Y.Y.0 is the network address for the LAN of docker e.g 192.168.1.0/24

ETH0 is your LAN interface

Z.Z.Z.Z is the Lan gateway i.e Your router IP most likely

Note that these commands don't survive a reboot. So if you would like to keep them, put them in /etc/rc.local with a "sleep 30" command.

Related Topic