OpenVPN

OpenVPN client docker container

What is OpenVPN?

OpenVPN is an open-source software application that implements virtual private network (VPN) techniques for creating secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities. It uses a custom security protocol that utilizes SSL/TLS for key exchange. It is capable of traversing network address translators (NATs) and firewalls.

How to use this image

This OpenVPN container was designed to be started first to provide a connection to other containers (using --net=container:openvpn, see below).

NOTE: More than the basic privileges are needed for OpenVPN. With docker 1.2 or newer you can use the --cap-add=NET_ADMIN and --device /dev/net/tun options. Earlier versions, or with fig, and you'll have to run it in privileged mode.

Hosting an OpenVPN client instance

sudo docker run --cap-add=NET_ADMIN --device /dev/net/tun --name openvpn \
            -v /some/path:/vpn -d dperson/openvpn \
            -v "vpn.server.name;username;password"
sudo cp /path/to/vpn.crt /some/path/vpn-ca.crt
sudo docker restart openvpn

Once it's up other containers can be started using it's network connection:

sudo docker run --net=container:openvpn -d some/docker-container

Configuration

sudo docker run -it --rm dperson/openvpn -h

Usage: openvpn.sh [-opt] [command]
Options (fields in '[]' are optional, '<>' are required):
    -h          This help
    -t ""       Configure timezone
                possible arg: "[timezone]" - zoneinfo timezone for container
    -v "<server;user;password>" Configure OpenVPN
                required arg: "<server>;<user>;<password>"
                <server> to connect to
                <user> to authenticate as
                <password> to authenticate with

The 'command' (if provided and valid) will be run instead of openvpn

ENVIROMENT VARIABLES (only available with docker run)

TIMEZONE - As above, set a zoneinfo timezone, IE EST5EDT
VPN - As above, setup a VPN connection

Examples

Timezone

Any of the commands can be run at creation with docker run or later with docker exec openvpn.sh (as of version 1.3 of docker).

sudo docker run --cap-add=NET_ADMIN --device /dev/net/tun --name openvpn \
            -v /some/path:/vpn -d dperson/openvpn -t EST5EDT \
            -v "vpn.server.name;username;password"
sudo cp /path/to/vpn.crt /some/path/vpn-ca.crt
sudo docker restart openvpn

Will get you the same settings as:

sudo docker run --cap-add=NET_ADMIN --device /dev/net/tun --name openvpn \
            -v /some/path:/vpn -d dperson/openvpn \
            -v "vpn.server.name;username;password"
sudo cp /path/to/vpn.crt /some/path/vpn-ca.crt
sudo docker restart openvpn
sudo docker exec openvpn openvpn.sh -t EST5EDT ls -AlF /etc/localtime
sudo docker restart openvpn

VPN configuration

In order to work you must provide VPN configuration and the certificate. You can use external storage for /vpn:

sudo docker run --cap-add=NET_ADMIN --device /dev/net/tun --name openvpn \
            -v /some/path:/vpn -d dperson/openvpn \
            -v "vpn.server.name;username;password"
sudo cp /path/to/vpn.crt /some/path/vpn-ca.crt
sudo docker restart openvpn

Or you can store it in the container:

cat /path/to/vpn.crt | sudo docker run -i --cap-add=NET_ADMIN \
            --device /dev/net/tun --name openvpn -d dperson/openvpn \
            -v "vpn.server.name;username;password" tee /vpn/vpn-ca.crt \
            >/dev/null
sudo docker restart openvpn

User Feedback

Issues

If you have any problems with or questions about this image, please contact me through a GitHub issue.

kevinschmidt/openvpn-client