docker-centos7-systemd-sshd

Docker-centos7-systemd-sshd.md

Docker centOS 7 based with systemd enabled and sshd installed.

Build image

docker build --rm -t c7-systemd-sshd .

Run

docker run --rm --privileged=true -p 22:22 -v /sys/fs/cgroup:/sys/fs/cgroup:ro c7-systemd-sshd

Alternatively you can use docker compose

Build

docker-compose build

Run

docker-compose run --service-ports --rm c7-systemd-sshd

In order to connect in the running container using ssh, obtain container_id running docker ps and run

docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' container_id

docker-compose.yml

version: '3'

services:
  c7-systemd-sshd:
    build: .
    ports:
      - "22:22"
    volumes: 
      - /sys/fs/cgroup:/sys/fs/cgroup:ro
    privileged: true
    networks:
      - c7_sshd_network
networks:
  c7_sshd_network:
    driver: bridge
    ipam:
      driver: default
      config:
        - subnet: 172.10.0.0/16

Dockerfile

FROM centos:7
ENV container docker

# remove some files to enable systemd
RUN (cd /lib/systemd/system/sysinit.target.wants/; for i in *; do [ $i == \
systemd-tmpfiles-setup.service ] || rm -f $i; done); \
rm -f /lib/systemd/system/multi-user.target.wants/*;\
rm -f /etc/systemd/system/*.wants/*;\
rm -f /lib/systemd/system/local-fs.target.wants/*; \
rm -f /lib/systemd/system/sockets.target.wants/*udev*; \
rm -f /lib/systemd/system/sockets.target.wants/*initctl*; \
rm -f /lib/systemd/system/basic.target.wants/*;\
rm -f /lib/systemd/system/anaconda.target.wants/*;
VOLUME [ "/sys/fs/cgroup" ]

RUN yum clean all && \
    yum -y install openssh-server openssh-clients initscripts

RUN ssh-keygen -f /etc/ssh/ssh_host_rsa_key -N '' -t rsa
RUN ssh-keygen -f /etc/ssh/ssh_host_ed25519_key -N '' -t ed25519
EXPOSE 22

# setup new root password
RUN echo root:pass | chpasswd

CMD ["/usr/sbin/init"]