Docker/Networking

Setting up networking between containers and host.

Stunnel

Stunnel networking configuration:

The stunnel server is running in a Docker container. Here is the stunnel server configuration file:

# server config,
# stunnel server will listen for stunnel clients connecting on port 443
# traffic will be decrypted and forwarded to local port 22

output	= /var/log/stunnel4/stunnel.log
cert	= /etc/stunnel/stunnel.fullchain.pem
key		= /etc/stunnel/stunnel.key.pem
pid		= /var/run/stunnel4/stunnel.pid
client	= no
[ssh]
accept	= 443
connect = 127.0.0.1:22

Note this is the same as is in the d-stunnel repo on git.charlesreid1.com: https://charlesreid1.com:3000/docker/d-stunnel

Stunnel server listens on port 443 (internal). This is mapped to port 443 (external) on the host using the -p 443:443 flag when executing docker run.

Stunnel forwards traffic on to 127.0.0.1 port 22. This port needs to be bound, somehow, to somewhere. Keep it simple: bind container port 22 (internal) to host port 22 (external) using -p 22:22 when executing docker run.

Network Equals Host Flag

Note that you can also configure the container to share networks with the host, by adding --network=host when executing docker run.