Setup a Docker on RHEL/CentOS and Debian/Ubuntu servers. The role supports Docker Engine's "Swarm Mode" (https://docs.docker.com/engine/swarm/) to create a cluster of Docker nodes.
An Ansible 2.3 or higher installation.
None.
Available variables are listed below, along with default values (see [defaults/main.yml](defaults/main.yml)):
docker_repo: "{{ docker_repo_ce_stable }}"
The repository proving the Docker packages.
The Docker Community stable repository is configured by default.
Additional repositories are defined in [vars/main.yml](vars/main.yml) including the edge, test and nightly repositories.
To skip the configuration of the repository and use the system repositories set skip_repo: true.
docker_package_name: "docker-ce"
Name of the package providing the Docker daemon.
docker_package_version: ""
Version of the Docker package to be installed on the target hosts.
When set to "" the latest available version will be installed.
docker_dependencies: "{{ default_docker_dependencies }}"
Additional packages to be installed by the role.
See [vars/RedHat.yml](vars/RedHat.yml) and [vars/Debian.yml](vars/Debian.yml) for the definition of the default_docker_dependencies variable.
docker_service_state: "started"
docker_service_enabled: "yes"
State of the Docker service.
docker_daemon_config: {}
Dictionary of Docker deamon configuration options to be written to /etc/docker/daemon.json.
See Daemon configuration file for the detailed documentation of the available options.
docker_swarm_interface: "{{ ansible_default_ipv4['alias'] }}"
Setting docker_swarm_interface allows you to define which network interface will be used for cluster inter-communication.
docker_swarm_addr: "{{ hostvars[inventory_hostname]['ansible_' + docker_swarm_interface]['ipv4']['address'] }}"
Listen address for the Swarm raft API.
By default, the ip address of docker_swarm_interface.
docker_swarm_port: 2377
Listen port for the Swarm raft API.
docker_group_name: "docker"
docker_group_users:
- "{{ ansible_user }}"
Name of the Docker group and list of users to be added to docker_group_name to manage the Docker daemon.
NB: The users must already exist in the system.
skip_repo: false
skip_engine: false
skip_group: false
skip_swarm: false
skip_docker_py: false
Switches allowing to disable specific functionalities of the role.
If you want to use this role to install docker-engine without enabling swarm-mode set skip_swarm: true.
Node labels provide a
flexible method of node organization. You can also use node labels in service constraints.
Apply constraints when you create a service to limit the nodes where the scheduler assigns tasks for the service.
You can define labels by swarm_labels variable, e.g:
$ cat inventory
...
[docker_swarm_manager]
swarm-01 swarm_labels=deploy
[docker_swarm_worker]
swarm-02 swarm_labels='["libvirt", "docker", "foo", "bar"]'
swarm-03
...
In this case:
$ docker inspect --format '{{json .Spec.Labels}}' swarm-02 | jq
{
"bar": "true",
"docker": "true",
"foo": "true",
"libvirt": "true",
}
You can assign labels to cluster running playbook with --tags=swarm_labels
NB: Please note, all labels that are not defined in inventory will be removed
$ cat inventory
swarm-01 ansible_ssh_host=172.10.10.1
swarm-02 ansible_ssh_host=172.10.10.2
swarm-03 ansible_ssh_host=172.10.10.3
[docker_engine]
swarm-01
swarm-02
swarm-03
[docker_swarm_manager]
swarm-01 swarm_labels=deploy
[docker_swarm_worker]
swarm-02 swarm_labels='["libvirt", "docker", "foo", "bar"]'
swarm-03
$ cat playbook.yml
- name: "Provision Docker Swarm Cluster"
hosts: all
roles:
- { role: atosatto.docker-swarm }
Tests are performed by Molecule.
$ pip install tox
To test all the scenarios run
$ tox
To run a custom molecule command
$ tox -e py27-ansible23 -- molecule test -s swarm-cluster
The MOLECULE_DRIVER_NAME and MOLECULE_TARGET_DISTRO allows to change the Molecule driver from Docker to Vagrant and the tests target OS
$ MOLECULE_DRIVER_NAME=vagrant MOLECULE_TARGET_DISTRO=ubuntu-1604 tox
To test the role on Ubuntu instead of CentOS set the
MIT
Andrea Tosatto (@_hilbert_)