Mail Server http://www.postfix.org/documentation.html
docker run --rm -p 25:25 fphammerle/postfixconfig docs: http://www.postfix.org/postconf.5.html
docker run --name postfix \
--volume $PWD/main.cf:/etc/postfix/main.cf:ro \
--detach --restart unless-stopped \
--security-opt=no-new-privileges \
--publish 25:25 \
fphammerle/postfixOptionally enable user namespace remapping via docker daemon option userns-remap.