linuxexpert-practice-labs/labs/ex294/2-3-static-inventories/README.md

EX294 2.3: Static inventories and groups

Write an inventory in INI and in YAML, with a group of groups and a group variable, and add the control node so its tasks run locally.

Before you start

This VM is the control node. The lab creates the user greg (password Lab-Pass-1) with an SSH key, and installs ansible-core. Work as greg, in /home/greg/ansible: its ansible.cfg reads the inventory ./inventory, which doesn't exist yet, and logs in as devops.

The managed nodes node1 (10.99.1.11), node2 (10.99.1.12) and node3 (10.99.1.13) are AlmaLinux 10 containers reached over SSH by name. On each, devops accepts greg's key. For a root shell on a node, sudo podman exec -it node1 bash.

Tasks

1. Write /home/greg/ansible/inventory in INI format, with node1 in group dev, node2 in test, node3 in prod, and a group webservers that contains the group prod. ansible-inventory --graph shows node3 under both prod and webservers, and ansible webservers --list-hosts lists node3.
2. Write the same inventory in YAML as /home/greg/ansible/inventory.yml, with a variable set on the dev group. ansible-inventory -i inventory.yml --graph --vars shows the same tree, with the variable on node1.
3. Add the control node to /home/greg/ansible/inventory as control, so tasks for it run locally: ansible control -a hostname prints this VM's name without SSH.

Hints

• [group:children] lists groups; [group:vars] sets variables.
• In YAML, hosts: and children: map names to their contents, even when empty: node1: with a trailing colon. Group variables go under vars:.
• ansible-inventory -y --list prints an INI inventory as YAML.
• ansible_connection=local on the host's line.
• ansible all -m ping checks every node answers.