Apologies if this is a known limitation of the GitLab runner/setup, but I haven't found any documentation suggesting this is the case. In my `.gitlab-ci.yml` I'm using `docker-compose` to start my application image along with a temporary MySQL service. The relevant job/stage of the build is: ``` test: image: craigotis/docker-c-npm:v1 stage: test script: - docker login -u gitlab-ci-token -p $CI_BUILD_TOKEN registry.gitlab.com/craigotis/myapp - docker images - docker-compose up -d - sleep 60 # temporary workaround to get 'logs' to work below - docker-compose logs - docker-compose port app 9143 - netstat -a - docker-compose ps - /usr/local/bin/wait-for-it.sh -h localhost -p 9143 -t 60 - cd mocha - npm i - npm test - docker-compose down ``` Note that if I run the `docker-compose up` on my local machine, it works fine and I can access port `localhost:9143` in a browser without issue. My `docker-compose.yml` file is fairly straightforward: ``` version: '2' networks: myapp_net: driver: bridge services: app: image: registry.gitlab.com/craigotis/myapp:latest depends_on: - "db" networks: - myapp_net command: wait-for-it.sh mysql_server:3306 -t 60 -- java -jar /opt/myapp*.jar ports: - "9143:9143" db: image: mysql:latest networks: - myapp_net container_name: mysql_server command: environment: - MYSQL_ALLOW_EMPTY_PASSWORD=true ``` The logs for the application image suggest it's listening: ``` app_1 | [Thread-1] INFO spark.webserver.SparkServer - == Spark has ignited ... app_1 | [Thread-1] INFO spark.webserver.SparkServer - >> Listening on 0.0.0.0:9143 app_1 | [Thread-1] INFO org.eclipse.jetty.server.Server - jetty-9.0.z-SNAPSHOT app_1 | [Thread-1] INFO org.eclipse.jetty.server.ServerConnector - Started ServerConnector@4e883fb1{HTTP/1.1}{0.0.0.0:9143} ``` However in my CI container, I cannot reach the port: ``` $ docker-compose port app 9143 0.0.0.0:9143 $ netstat -a Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 runner-4e4528ca-project-1925166-concurrent-0:38542 docker:2375 TIME_WAIT tcp 0 0 runner-4e4528ca-project-1925166-concurrent-0:38540 docker:2375 TIME_WAIT Active UNIX domain sockets (servers and established) Proto RefCnt Flags Type State I-Node Path $ docker-compose ps stty: standard input: Not a tty Name Command State Ports ------------------------------------------------------------------------------ myapp_1 wait-for-it.sh mysql_serve ... Up 0.0.0.0:9143->9143/tcp mysql_server docker-entrypoint.sh --cha ... Up 3306/tcp $ /usr/local/bin/wait-for-it.sh -h localhost -p 9143 -t 60 wait-for-it.sh: waiting 60 seconds for localhost:9143 wait-for-it.sh: timeout occurred after waiting 60 seconds for localhost:9143 ``` Is there a trick to using `docker-compose` within a CI build stage to open ports to the CI container itself?