FROM arm32v6/alpine:3.8 RUN apk add --no-cache openssh-client COPY entrypoint.sh / RUN chmod a+rx /entrypoint.sh ENTRYPOINT ["/entrypoint.sh"] COPY ssh_config /etc/ssh/ssh_config RUN chmod a=r /etc/ssh/ssh_config RUN adduser -S tunnel COPY known_hosts /home/tunnel/.ssh/known_hosts RUN chown tunnel /home/tunnel/.ssh/known_hosts USER tunnel ENV BIND_ADDRESS bind-address CMD ssh -T -R $BIND_ADDRESS:22:$DOCKER_HOST_ADDRESS:22 serveo.net