Errno::EACCES creating rails project using Docker Rails image

I’m trying to use the official Rails image for Docker to create my development environment and after creating the container using docker build -t my-rails-app . I tried to bootstrap the new app using this command: docker run -it –rm –user “$(id -u):$(id -g)” -v “$PWD”:/usr/src/app -w /usr/src/app rails rails new –skip-bundle webapp And got […]

Bad docker tag got daemon stuck

I seem to have a container that is stuck in a bad state that I dont know how to get out of. $ docker ps -qa Error response from daemon: Error parsing reference: “demoapp:feature/blue.background” is not a valid repository/tag I think this offending container was created months ago. Is there any way I can delete […]

How do I migrate my current deployment methodology to one using Docker?

This is going to be a bit of along question, so be forewarned. The short version: Our current deployment system uses Fabric and Git to deploy a Python web application and supporting parts. The system works well but after spending 2 weeks working to extend it I realised I was essentially trying to re-invenĖ†t the […]

How to build a large docker image with relatively small disk space consumption?

Background I am trying to build a docker image from Dockerfile on a VM. VM is running Redhat 7.1 (kernel 3.10) and Docker is 1.10.2 The Dockerfile has following content FROM rhel MAINTAINER MyName<me@email.com> RUN #yum install wget and other tools (less than 500 MB) COPY entitlementfile /opt/entitlementfile RUN wget -O /opt/installer.bin https://installer.com/installer.bin \ && […]

docker container not finding the unix socket

I have a docker container from which I want to spawn a new container. I am using com.spotify:docker-client:3.3.5 for communications. The output of docker version is shown below, as is the output from docker images and the echo to the docker unix socket. The code I am running is final DockerClient docker = DefaultDockerClient.builder() .uri(URI.create(“unix:///var/run/docker.sock”)).build(); […]

Memory snappiness docker

I have installed Docker 1.8.1 on Debian 8.1. When I run docker info, I get: WARNING: No memory limit support WARNING: No swap limit support There is a trick to enable memory swappiness: https://docs.docker.com/installation/ubuntulinux/#adjust-memory-and-swap-accounting It is written on the above documentation that enabling memory swappiness does degrade performance. Why should I enable this option if […]

Docker Networking

I am trying to understand the relationship between: eth0 on the host machine; and docker0 bridge; and eth0 interface on each container It is my understanding that Docker: Creates a docker0 bridge and then assigns it an available subnet that is not in conflict with anything running on the host; then Docker binds docker0 to […]

Docker Compose – Not picking up the dump file in the init command?

I have following syntax in windows based docker enr. however when i run the docker-compose up it loads the container however don’t load the dump file inside the dump file location given as the entry-point to the mysql process. any ideas ? below is the my docker-compose.yml file. mysql: image: mysql:latest volumes_from: – data environment: […]

Unable to get Maven version from /usr/share/maven/bin/mvn Could not find system variable

I want to run bamboo remote agent using docker . When i run the image atlassian/bamboo-java-agent in my machine it produces the following error Unable to get Maven version from /usr/share/maven/bin/mvn Could not find system variable If you wish to use perforce please set the location as a capability. How to solve these two errors? […]

docker-compose – unable to attach to containers

Using below docker-compose.yml file if I run “docker-compose up” or “docker-compose up -d” command then I see both containers status as exited however when I run docker restart <postgres-containerId> then its up and running but when I try to run docker restart <java8-containerId> then its restarting and again exiting. Could you please suggest what parameter […]

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