FROM alpine:3.13.5 ARG OPENSSH_SERVER_PACKAGE_VERSION=8.4_p1-r3 RUN apk add --no-cache openssh-server=$OPENSSH_SERVER_PACKAGE_VERSION ENV SSHD_HOST_KEYS_DIR /etc/ssh/host_keys VOLUME $SSHD_HOST_KEYS_DIR COPY sshd_config /etc/ssh/sshd_config # comma-separated list of usernames ENV USERS "" EXPOSE 22/tcp COPY entrypoint.sh / ENTRYPOINT ["/entrypoint.sh"] CMD ["/usr/sbin/sshd", "-D", "-e"]