This charm deploys the Docker engine within Juju. Docker is an open platform for developers and sysadmins to build, ship, and run distributed applications in containers.
Docker containers wrap a piece of software in a complete file system that contains everything needed to run an application on a server.
Docker focuses on distributing applications as containers that can be quickly assembled from components that are run the same on different servers without environmental dependencies. This eliminates the friction between development, QA, and production environments.
Most people will want to extend this charm to make their Docker container or application deployable from Juju. The Charm layer can be extended to include docker container along with additional operational code. Please refer to the Charm Layers documentation on jujucharms.com for more information.
Docker does not require anything by default so you can deploy the Charm by the following command.
juju deploy docker
NOTE: You can ask Juju to deploy a different release of Ubuntu by using the
--series and the code name of the release "trusty" for 14.04 and "xenial" for
16.04.
Once deployed you have a docker-engine running on a unit in Juju. You can open
a session to that unit and issue the docker command to start using it
right away.
juju ssh docker/0
...
$ docker run hello-world
Scaling out the Charm is as simple as adding additional docker units
with Juju add-unit command to expand your cluster. However, you will need an
SDN solution to provide cross host networking. See the Known Limitations and
issues about this.
- docker-opts : Pass through configuration to the docker daemon, such as configuring the docker daemon to allow an insecure private registry.
juju config docker docker-opts='--insecure-registry=http://my.insecure.registry:5000'
-
enable-cgroups = (false) : To enable memory and swap on system using GNU GRUB (GNU GRand Unified Bootloader) set this value to 'true'. It updates the
/etc/default/grubfile settingGRUB_CMDLINE_LINUXtocgroup_enable=memory swapaccount=1. The default value is 'false'. WARNING: changing this option will initiate a reboot of the host - use with caution on as your containers will shutdown when this configuration value is set. -
http_proxy : The string URL that will set the HTTP_PROXY environment variable for Docker containers. Useful in environments with restricted networks where a proxy is the only route to the registry to pull images. Setting this option forces the Docker daemon to restart.
-
https_proxy : The string URL that will set the HTTPS_PROXY environment variable for Docker containers. Useful in environments with restricted networks where a proxy is the only route to the registry to pull images. Setting this option forces the Docker daemon to restart.
-
no_proxy : The comma-separated list of destinations (domain names or IP addresses) that will set the NO_PROXY environment variable for Docker containers. Useful in environments with restricted networks where a proxy is the only route to the registry to pull images, but you still need to access a few domains directly (e.g. an internal, private registry). Setting this option forces the Docker daemon to restart.
This Charm also installs the 'docker-compose' python package using pip. So once the Charm has finished installing you have the ability to use Docker Compose functionality such as control files, and logging.
This Charm is available at https://jujucharms.com/docker and contains the open source operations code to deploy on all public clouds in the Juju ecosystem.
- The Docker homepage
- Docker documentation for help with Docker commands.
- Docker forums for community discussions.
- Check the Docker issue tracker for bugs or problems with the Docker software.
- The layer-docker is the GitHub repository that contains the reactive code to build this Charm.
- Check the layer-docker issue-tracker for bugs or problems related to the Charm.