How to setup controller node ansible

Table of contents

Intro

ansible wrote in python, so we need python 2.7 or python 3.8 higher to run ansible properly. many given methods to install ansible, here I wanna share with you to setup controller node ansible with pip.

pip is a python package manager, we use pip because is simple and we can keep it isolated with virtualenv. to install the latest pip type and run the following command.

$ sudo apt install python3-pip

and we need virtualenv too to create an isolated environment.

$ pip install virtualenv

and let’s create a virtual environment with virtualenv and activated it with the command below.

$ virtualenv ansible; source ~/ansible/bin/activate

next, we can install ansible with pip install

(ansible)$ pip install ansible

if virtualenv activated check ansible has been installed properly with the following command

(ansible)$ ansible --version

if no error found, congratulations you succeed in installing ansible on the controller node next, we can try the simple playbook and configure the Ansible inventory. Inventory is simply explained as a list or group of managed nodes. for example, we have two managed nodes called worker and master, and we can type like this.

[master]
node-master ansible_host=192.168.2.2 ansible_user=ansible
[worker]
worker-1 ansible_host=192.168.2.3 ansible_user=ansible
worker-2 ansible_host=192.168.2.4 ansible_user=ansible

for grouping identified with sign [nameofgroup]. pro tips we can also define an ip host and default user for ssh.

ansible run task on playbook. here an example playbook for installing docker with ansible.

Playbooks are Ansible’s configuration, deployment, and orchestration language. They can describe a policy you want your remote systems to enforce, or a set of steps in a general IT process. ansible playbook have 2 basic component, first is hosts and users setup, you can be spesify spesific node or just call group name that has been configured in inventory file. Second is tasks list, task would be executed in order, one at time, agains all machine matched by the host pattern, before moving on to the next task. tasks contains collections, and modules.

before we run the playbook file, we can check playbook no have file, roles, or syntax problem. run with the --syntax-check flag.

(ansible)$ ansible-playbook --syntax-check docker.yml

if no errors found we can run ansible playbook with following command, add -i for inventory path, by default ansible read /etc/ansible/hosts

(ansible)$ ansible-playbook -i path docker.yml