Docker image with ssh server

container-runner

#!/bin/bash
NAME=linuxserver
MASTER_NAME=sshd
if [[ -z "$2" ]]; then
	EXTERNAL_PORT=2022
else
	EXTERNAL_PORT=$2
fi


export NAME=$NAME
export EXTERNAL_PORT=$EXTERNAL_PORT
sudo -E /opt/docker-runners/runners-default/master-$MASTER_NAME $1

Dockerfile

FROM oraclelinux:6.6
MAINTAINER Konstantin Neradovsky "kneradovsky@gmail.com"

RUN yum install -y openssh-server sudo passwd
ADD run /usr/local/bin/run
ADD adminuser /etc/sudoers.d/adminuser
RUN ssh-keygen -f /etc/ssh/ssh_host_rsa_key -N '' -t rsa
RUN ssh-keygen -f /etc/ssh/ssh_host_dsa_key -N '' -t dsa
RUN echo 123qweasd | passwd --stdin root 
RUN useradd -G root adminuser
RUN echo 123qwe | passwd --stdin adminuser
RUN chmod +x /usr/local/bin/run
CMD ["/usr/local/bin/run"]

master-sshd

#!/bin/bash
LOGS="tail -n 200 -f  /var/log/messages"
CONSOLE="bash"
INTERNAL_PORT=22
PREFIX=sshdserver
CID=$EXTERNAL_PORT
HELP_MESSAGE="USAGE: $NAME <start, stop, remove, logs, console  or status> [ID]"
if [[ -z "$1" ]]; then 
	echo $HELP_MESSAGE
	exit 0
fi


if [ $1 == "start" ]; then
	docker run -p $EXTERNAL_PORT:$INTERNAL_PORT --privileged -d -t --name $NAME-$CID oraclelinux:$PREFIX
	docker start $NAME-$CID
	echo "container started"
elif [ $1 == "stop" ]; then
	docker stop $NAME-$CID
	echo "Container stopped"
elif [ $1 == "remove" ]; then
	docker stop $NAME-$CID
	docker rm $NAME-$CID
	echo "container removed"
elif [ $1 == "status" ];then
	docker ps|grep "NAMES" && docker ps -a|grep "$NAME-$CID"
elif [ $1 == "logs" ];then
        lxc-attach -n `sudo docker inspect $NAME-$CID | grep '"ID"' | sed 's/[^0-9a-z]//g'` -- $LOGS
elif [ $1 == "console" ];then
        lxc-attach -n `sudo docker inspect $NAME-$CID | grep '"ID"' | sed 's/[^0-9a-z]//g'` -- $CONSOLE
else
	echo $HELP_MESSAGE
fi

run

#!/bin/bash
set -e

exec /usr/sbin/sshd -D

Why

Sometime you need discardable environment to play with. Docker containers could be lightweight alternative to the regular vm snapshots. The container will start ssh server in foregorund letting you to login inside from outside of the docker host.

How to use

1. Clone gist to folder sshdserver , cd to the folder
2. Change line 1 in docker file to the name of your base image.
3. Create docker image using dockerfile sudo docker build -t tag-your-image
4. Change path of the master-sshd script on the line 13 of the container-run to the sshdserver folder
   5 . start docker using ./container-run start if portnum is omitted default value 2022 is used
5. login into the container slogin -P portnum adminuser@dockerhosr. The password is 123qwe