I'm having a problem with MySQL running inside a Docker container. My testing image is built from the following Dockerfile:
# See: https://index.docker.io/u/brice/mysql/ FROM ubuntu:12.10 MAINTAINER Joni Kahara <email@example.com> # Because docker replaces /sbin/init: https://github.com/dotcloud/docker/issues/1024 RUN dpkg-divert --local --rename --add /sbin/initctl RUN ln -s /bin/true /sbin/initctl RUN apt-get update RUN apt-get upgrade -y RUN apt-get -y install mysql-server RUN sed -i -e"s/^bind-address\s*=\s*127.0.0.1/bind-address = 0.0.0.0/" /etc/mysql/my.cnf RUN /usr/bin/mysqld_safe & \ sleep 10s && \ mysql -e "GRANT ALL ON *.* to 'root'@'%'; FLUSH PRIVILEGES;" EXPOSE 3306 VOLUME ["/var/lib/mysql", "/var/log/mysql"] CMD ["mysqld_safe"]
After building an image from the file above, I run it with:
docker run -p 3306:3306 asyncfi/magento-mysql
After which everything is swell and I can log in to this instance of MySQL from the local machine. However, I can also log in from any other machine.
I have set up my firewall to filter everything except traffic coming in to specific ports ("hidden" SSH, HTTP, HTTPS), and this filtering does in fact seem to work; if I for example run a Django development server on port 1234 then I am able to connect from the local machine, but not from outside. So the firewall seems to be filtering packets when they're destined to a server that is running as a "plain" process, but not when the server is running inside a container.
iptables -L -v --line-numbers says the following:
Chain INPUT (policy ACCEPT 0 packets, 0 bytes) num pkts bytes target prot opt in out source destination 1 2265 107K ACCEPT all -- lo any anywhere anywhere 2 240K 319M ACCEPT all -- any any anywhere anywhere ctstate RELATED,ESTABLISHED 3 14 1040 ACCEPT tcp -- any any anywhere anywhere tcp dpt:<REDACTED> 4 21 1092 ACCEPT tcp -- any any anywhere anywhere tcp dpt:http 5 6 360 ACCEPT tcp -- any any anywhere anywhere tcp dpt:https 6 538 34656 LOG all -- any any anywhere anywhere limit: avg 5/min burst 5 LOG level debug prefix "iptables DROP: " 7 551 35424 DROP all -- any any anywhere anywhere Chain FORWARD (policy ACCEPT 5 packets, 296 bytes) num pkts bytes target prot opt in out source destination 1 0 0 ACCEPT all -- docker0 docker0 anywhere anywhere 2 6752 396K ACCEPT all -- docker0 !docker0 anywhere anywhere 3 125K 188M ACCEPT all -- any docker0 anywhere anywhere ctstate RELATED,ESTABLISHED Chain OUTPUT (policy ACCEPT 51148 packets, 14M bytes) num pkts bytes target prot opt in out source destination
Docker version is:
Client version: 0.7.3 Go version (client): go1.2 Git commit (client): 8502ad4 Server version: 0.7.3 Git commit (server): 8502ad4 Go version (server): go1.2 Last stable version: 0.7.3
Why is the MySQL port exposed to the outside world?