Docker: Difference between revisions

From Alpine Linux
(improved existing format, added info about installing docker-compose)
(improved docker install instructions. validated and uncommented grsecurity flags with proper description and link to docker-github-issue)
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docker.com has excellent walk-throughs on how to run, pull, setup a container, commit an image, and create a configuration file.  hub.docker.com is a freemium setup, where the first private repository is free.
docker.com has excellent walk-throughs on how to run, pull, setup a container, commit an image, and create a configuration file.  hub.docker.com is a freemium setup, where the first private repository is free.


== To install from Alpine ==
== Installation ==


   
   
<code>apk add docker</code>
Run <code>apk add docker</code> to install Docker on Alpine Linux.


The Docker package is in the 'Community' repository, so if the '''apk add''' fails with '''unsatisfiable constraints''', you need to edit the '''/etc/apk/repositories''' file to add (or uncomment) a line like:
The Docker package is in the 'Community' repository, so if the '''apk add''' fails with '''unsatisfiable constraints''', you need to edit the '''/etc/apk/repositories''' file to add (or uncomment) a line like:
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<code>rc-update add docker boot</code>
<code>rc-update add docker boot</code>


<!--
you'll need to disable some kernel security flags:
'''
sysctl -w kernel.grsecurity.chroot_caps=0
sysctl -w kernel.grsecurity.chroot_deny_chmod=0
sysctl -w kernel.grsecurity.chroot_deny_chroot=0
sysctl -w kernel.grsecurity.chroot_deny_mknod=0
sysctl -w kernel.grsecurity.chroot_deny_mount=0
'''
-->


'''Then to start the Docker daemon manually, run:'''
'''Then to start the Docker daemon manually, run:'''


<code>service docker start</code>
<code>service docker start</code>
{{Note|You'll need to disable some kernel security flags in order to build images:}}
<code>sysctl -w kernel.grsecurity.chroot_deny_chmod=0</code>
<code>sysctl -w kernel.grsecurity.chroot_deny_mknod=0</code>
For more information, have a look at the [https://github.com/docker/docker/issues/20303 corresponding Github issue].


=== Docker Compose ===
=== Docker Compose ===

Revision as of 21:50, 29 April 2016

Alpine makes a great docker container, because it is so small and optimized to be run in RAM. It might also might make a good controller for several docker containers with enough RAM. I haven't tested this yet Docker's setup is easy to use from command line. Commands can be run from an interactive shell, or through a configuration file called a "Dockerfile". docker.com has excellent walk-throughs on how to run, pull, setup a container, commit an image, and create a configuration file. hub.docker.com is a freemium setup, where the first private repository is free.

Installation

Run apk add docker to install Docker on Alpine Linux.

The Docker package is in the 'Community' repository, so if the apk add fails with unsatisfiable constraints, you need to edit the /etc/apk/repositories file to add (or uncomment) a line like:

http://dl-6.alpinelinux.org/alpine/edge/community


To start the Docker daemon at boot, run:

rc-update add docker boot


Then to start the Docker daemon manually, run:

service docker start


Note: You'll need to disable some kernel security flags in order to build images:

sysctl -w kernel.grsecurity.chroot_deny_chmod=0

sysctl -w kernel.grsecurity.chroot_deny_mknod=0

For more information, have a look at the corresponding Github issue.

Docker Compose

To install docker-compose, first install pip:

apk add py-pip


Then install docker-compose, run:

pip install docker-compose


Example: How to install docker from Arch

https://wiki.archlinux.org/index.php/Docker


How to use docker

The best documentation for how to use Docker and create containers is at the main docker site. Adding anything more to it here would be redundant.

http://docs.docker.com/

if you create an account at docker.com you can browse through other user's images and learn from the syntax in contributor's dockerfiles.

Official Docker image files are denoted by a blue ribon on the website.