Introduction
Custom facts let managed hosts publish local data to Ansible. Facts placed under /etc/ansible/facts.d become available through ansible_local after fact gathering.
In this lab, you will install a small custom fact file and use it in a second play to render a report.
Create a Custom Fact Project
In this step, you will create a project for installing and reading a custom fact.
cd /home/labex/project
mkdir -p rhce-ansible/{inventory,files,playbooks,reports}
cd rhce-ansible
cat > ansible.cfg <<'EOF'
[defaults]
inventory = ./inventory/hosts
host_key_checking = False
retry_files_enabled = False
EOF
cat > inventory/hosts <<'EOF'
[managed]
host ansible_connection=local
EOF
Custom facts are installed on the managed host, so this lab needs both a source file under the project and a playbook that copies it into /etc/ansible/facts.d.
Create a Local Fact Source File
In this step, you will create an INI-style fact file. The section name and keys will appear under ansible_local.rhce_custom.general.
Before running commands in this step, return to the Ansible project directory. This keeps the commands stable even when LabEx runs each step separately.
cd /home/labex/project/rhce-ansible
cat > files/rhce_custom.fact <<'EOF'
[general]
course=rhce-ansible
track=custom-facts
EOF
The file uses INI-style syntax. After fact gathering, the section name general and its keys become available under ansible_local.rhce_custom.general.
cat files/rhce_custom.fact
Write a Playbook that Installs and Reads the Fact
In this step, you will write a two-play playbook. The first play installs the fact file with privilege escalation; the second play gathers facts again so ansible_local includes the new data.
Before running commands in this step, return to the Ansible project directory. This keeps the commands stable even when LabEx runs each step separately.
cd /home/labex/project/rhce-ansible
cat > playbooks/custom-fact.yml <<'EOF'
---
- name: Install custom fact
hosts: managed
become: true
gather_facts: false
tasks:
- name: Ensure facts directory exists
ansible.builtin.file:
path: /etc/ansible/facts.d
state: directory
mode: '0755'
- name: Install RHCE custom fact
ansible.builtin.copy:
src: ../files/rhce_custom.fact
dest: /etc/ansible/facts.d/rhce_custom.fact
mode: '0644'
- name: Read custom fact after gathering facts
hosts: managed
gather_facts: true
tasks:
- name: Write custom fact report
ansible.builtin.copy:
dest: /home/labex/project/rhce-ansible/reports/custom-fact.txt
content: |
course={{ ansible_local.rhce_custom.general.course }}
track={{ ansible_local.rhce_custom.general.track }}
mode: '0644'
EOF
The first play installs the fact file with become because /etc/ansible/facts.d is a system path. The second play gathers facts again; without that second gather, ansible_local would not include the newly installed fact in the same run.
ansible-playbook playbooks/custom-fact.yml --syntax-check
Run the Custom Fact Playbook
In this step, you will install the custom fact and render a report from ansible_local. The first play modifies system fact storage, and the second play proves Ansible can read it. Before running commands in this step, return to the Ansible project directory. This keeps the commands stable even when LabEx runs each step separately.
cd /home/labex/project/rhce-ansible
ansible-playbook playbooks/custom-fact.yml | tee reports/custom-fact-run.txt
The first run should change the system by installing the fact file and writing the report. The saved output is useful if the second play cannot find ansible_local.
cat reports/custom-fact.txt
The report should contain the course and track values from the local fact file, proving Ansible gathered and used the custom fact.
Inspect ansible_local Directly
In this step, you will use the setup module with a filter to view the custom fact tree directly.
Before running commands in this step, return to the Ansible project directory. This keeps the commands stable even when LabEx runs each step separately.
cd /home/labex/project/rhce-ansible
ansible managed -m ansible.builtin.setup -a 'filter=ansible_local' | tee reports/ansible-local.txt
The setup module output is the raw fact tree. Filtering to ansible_local keeps the output focused on locally supplied custom facts.
grep -E 'rhce_custom|custom-facts|rhce-ansible' reports/ansible-local.txt
The grep output should show the custom fact name and the values you wrote. This is the direct inspection path to use when a playbook cannot see ansible_local.
Summary
You installed a host-local custom fact, gathered facts again, used ansible_local in a playbook, and inspected the custom fact through the setup module.
