(original answer see below) Update Sept. 2016: Docker 1.13: PR 26108 and commit 86de7c0 introduce a few new commands to help facilitate visualizing how much space the docker daemon data is taking on disk and allowing for easily cleaning up “unneeded” excess. docker system prune will delete ALL dangling data (i.e. In order: containers stopped, … Read more
There are a couple ways you can do this. The simplest way to do so is to use the dockerfile ADD command like so: ADD . /path/inside/docker/container However, any changes made to this directory on the host after building the dockerfile will not show up in the container. This is because when building a container, … Read more
The contents of the /var/lib/docker directory vary depending on the driver Docker is using for storage. By default this will be aufs but can fall back to overlay, overlay2, btrfs, devicemapper or zfs depending on your kernel support. In most places this will be aufs but the RedHats went with devicemapper. You can manually set … Read more
The –format option of inspect comes to the rescue. Modern Docker client syntax is: docker inspect -f ‘{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}’ container_name_or_id Old Docker client syntax is: docker inspect –format ‘{{ .NetworkSettings.IPAddress }}’ container_name_or_id These commands will return the Docker container’s IP address. As mentioned in the comments: if you are on Windows, use double quotes ” instead … Read more
You just need to make sure that the containers you want to talk to each other are on the same network. Networks are a first-class docker construct, and not specific to compose. # front/docker-compose.yml version: ‘2’ services: front: … networks: – some-net networks: some-net: driver: bridge … # api/docker-compose.yml version: ‘2’ services: api: … networks: … Read more
/sbin/ip route|awk ‘/default/ { print $3 }’ As @MichaelNeale noticed, there is no sense to use this method in Dockerfile (except when we need this IP during build time only), because this IP will be hardcoded during build time.
Basically, you have three options: Neither specify EXPOSE nor -p Only specify EXPOSE Specify EXPOSE and -p 1) If you specify neither EXPOSE nor -p, the service in the container will only be accessible from inside the container itself. 2) If you EXPOSE a port, the service in the container is not accessible from outside … Read more
The cp command can be used to copy files. One specific file can be copied TO the container like: docker cp foo.txt container_id:/foo.txt One specific file can be copied FROM the container like: docker cp container_id:/foo.txt foo.txt For emphasis, container_id is a container ID, not an image ID. (Use docker ps to view listing which … Read more
You can simply install a vncserver along with Firefox 🙂 I pushed an image, vnc/firefox, here: docker pull creack/firefox-vnc The image has been made with this Dockerfile: # Firefox over VNC # # VERSION 0.1 # DOCKER-VERSION 0.2 FROM ubuntu:12.04 # Make sure the package repository is up to date RUN echo “deb http://archive.ubuntu.com/ubuntu precise … Read more
You can copy your crontab into an image, in order for the container launched from said image to run the job. See “Run a cron job with Docker” from Julien Boulay in his Ekito/docker-cron: Let’s create a new file called “hello-cron” to describe our job. # must be ended with a new line “LF” (Unix) … Read more