Docker Cannot link to a non running container

Question

I need to create Rails and Mysql containers with docker-compose. When I try to create links between containers with docker-compose up, I get

Cannot start container 9b271c58cf6aecaf017dadaf5b Cannot link to a non running container: /puma_db_1 AS /puma_web_1/db

Files

Dockerfile

FROM ubuntu:14.04  RUN apt-get -y update RUN apt-get -y install git curl zlib1g-dev build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev python-software-properties libffi-dev  RUN apt-get -y install libmysqlclient-dev RUN git clone https://github.com/sstephenson/rbenv.git /root/.rbenv RUN git clone https://github.com/sstephenson/ruby-build.git /root/.rbenv/plugins/ruby-build RUN echo 'eval "$(rbenv init -)"' >> $HOME/.profile RUN echo 'eval "$(rbenv init -)"' >> $HOME/.bashrc  RUN rbenv install 2.1.5 RUN rbenv global 2.1.5 RUN gem install rails -v 4.0.11  ADD app.tar.gz /home/ WORKDIR /home/app  RUN bundle install EXPOSE 3000 CMD ["rails", "server", "-b", "0.0.0.0"] 

docker-compose.yml

db:     image: mysql:latest   environment:     MYSQL_DATABASE: app_development     MYSQL_USER: mysql     DATABASE_PASSWORD: onetwo     ROOT_PASSWORD: onetwo web:   build: .   command: bundle exec rails s -p 3000 -b '0.0.0.0'   ports:     - "4000:3000"   links:     - db 

Answer 1

Most likely the db container fails to start.

Make sure it works fine by starting only the db service. You can do that with the following command:

docker-compose up db 

If it appears the MySQL service is not running after this command, then you found the origin of your problem.

Answer 2

Not specifically related to MySQL but more the message ERROR: for <service> Cannot link to a non running container: /b2f21b869ccc_<dependency>_1 AS /<service>_1/<dependency>_1

I found that the dependency container had a different id than the one given (b2f21b869ccc in my example above)

Solved simply by running docker-compose up -d --force-recreate <service>

which caused it to recreate the dependency and fix the link to the correct docker id