install_node_exporter.yaml

---
- hosts: localhost
  name: Install node_exporter on RHEL8
  become: true
  tasks:

    - name: Add user node_exporter
      user:
        name: node_exporter
        shell: /bin/false
        system: true
        create_home: no

    - name: Download and extract 
      unarchive:
        src: https://github.com/prometheus/node_exporter/releases/download/v0.18.1/node_exporter-0.18.1.linux-amd64.tar.gz
        dest: /tmp
        remote_src: yes

    - name: Copy bin node_exporter to /usr/local/bin
      copy:
        src: /tmp/node_exporter-0.18.1.linux-amd64/node_exporter
        dest: /usr/local/bin/
        owner: node_exporter
        group: node_exporter
        mode: u+x,g+x,o+x    

    - name: Create service node_exporter.service
      blockinfile:
        path: /etc/systemd/system/node_exporter.service
        block: |
          [Unit]
          Description=Prometheus Node Exporter
          Wants=network-online.target
          After=network-online.target

          [Service]
          User=node_exporter
          Group=node_exporter
          Type=simple
          ExecStart=/usr/local/bin/node_exporter

          [Install]
          WantedBy=multi-user.target
        create: true

    - name: systemctl daemon_reload
      systemd:
        daemon_reload: yes

    - name: Start and Enable node_exporter
      service:
        name: node_exporter
        state: started
        enabled: yes

    - name: Check whether port 9100 is available
      wait_for:
        port: 9100
        state: started
        timeout: 5