Ansible role - Node Exporter

Node Exporter role is designed to simplify the installation and configuration of Node Exporter on various Linux distributions. Node Exporter is a popular Prometheus exporter that collects hardware and operating system metrics from Linux systems.

This role provides a straightforward way to deploy Node Exporter across systems from the Red Hat Enterprise Linux (RHEL) family, including RHEL 8, RHEL 9, Rocky Linux, Alma Linux, CentOS, and Fedora. It has been tested extensively on RHEL 8 and RHEL 9, ensuring compatibility and reliability.

Role support two scenarios:

• Deployment: This scenario is idempotent and ensures that Node Exporter is in the required state (present). It installs and configures Node Exporter on the target system.
• Uninstall: This scenario ensures that everything deployed by the role is removed and cleaned up (uninstall). It removes Node Exporter from the target system.

Role Key feature:

• Easy Installation/Uninstall: The role simplifies the installation and uninstallation processes for Node Exporter, making it quick and hassle-free.
• Customizable Configuration: The role provides various configuration options that can be customized according to your needs. This allows you to tailor the deployment of Node Exporter to suit your specific requirements.
• Version Flexibility: Allowing users to set the version to either “latest” or a specific version like “1.6.0”. This simple and intuitive feature empowers users to easily control the Node Exporter version according to their deployment requirements.

📢 Check the blog post 📝 Experience a step-by-step demo of deploying and uninstalling Node Exporter using my Ansible role.

Requirements

No requirements

Role Variables

• Default Variables. Usually, there is no need to change this but rather overwrite the value in host_vars or group_vars if required.

Variable Name	Default Value	Description
node_exporter_version	"latest"	The version of Node Exporter to download and deploy. Supported standard version "1.6.0" format or "latest".
node_exporter_binary_path	/usr/local/bin	The path where the Node Exporter binary is located.
node_exporter_user	"node_exporter"	The user under which the Node Exporter service runs. This user is marked as a system user.
node_exporter_group	"node_exporter"	The system group associated with the Node Exporter service.
node_exporter_web_listen_address	"0.0.0.0"	The address on which Node Exporter listens for HTTP requests. By default, it listens on all interfaces.
node_exporter_listen_port	9100	The TCP port on which Node Exporter listens for incoming connections. By default, it listens on port 9100.
node_exporter_expose_port	true	Set to true by default, controls whether to add a firewalld rule for exposing the Node Exporter port. When true, a firewalld rule is added to allow inbound traffic on the specified Node Exporter port. Set to false to ensure that firewalld rule is not present.
node_exporter_arch	"amd64"	The architecture of the Linux system for which Node Exporter is being deployed.
node_exporter_download_url	https://github.com/ prometheus/ node_exporter/releases/ download/ v{{ node_exporter_version }} /node_exporter- {{ node_exporter_version }} .linux- {{ node_exporter_arch }}.tar.gz	The default download URL for the Node Exporter package from GitHub.

• group_vars or host_vars variables.

Variable Name	Example Usage	Required	Description
node_exporter_runtime_flags	node_exporter_runtime_flags:  - "--collector.textfile.directory {{ node_exporter_textfile_path }}"  - "--collector.systemd"  - "--collector.network_route"	No	Optional execution flags injected into the systemd unit file for Node Exporter. You can refer to the official node exporter Github repo to obtain a list of available collectors.
node_exporter_textfile_path	"/var/lib/node_exporter"	NO(required when runtime flag textfile is defined)	If you define the --collector.textfile.directory flag in the node_exporter_runtime_flags variable, it is required to specify the directory path. By default, the directory is not created. The textfile collector serves a specific purpose as explained in the provided link.

Dependencies

No Dependencies

Deployment and Uninstall Playbook

• Deployment playbook (function_node-exporter_deploy.yml)

- name: Deploy node_exporter service
  hosts: node_exporter
  gather_facts: false
  become: true
  roles:
    - role: node_exporter
      state: present

• Uninstall playbook (function_node-exporter_uninstall.yml)

- name: Uninstall node_exporter service
  hosts: node_exporter
  gather_facts: false
  become: true
  roles:
    - role: node_exporter
      state: absent

Example Execution

• Deployment playbook

ansible-playbook -i inventory/hosts function_node-exporter_deploy.yml

• Uninstall playbook. Ensure that you provided limit to remove only specified host!

ansible-playbook -i inventory/hosts function_node-exporter_uninstall.yml --limit "node2.voidquark.com"

Directory Structure Example

Here is an example of how you can organize your files using a directory structure for your Ansible project. This structure demonstrates where to place the playbook (deploy/uninstall), the inventory file, and where to include this role.

ansible_structure
├── automation
│   ├── function_node-exporter_deploy.yml # Deployment playbook
│   ├── function_node-exporter_uninstall.yml # Uninstall playbook
│   └── roles # Clone this role in to this dir.
│       └── node_exporter
└── inventory
    ├── group_vars
    │   └── node_exporter
    │       └── node_exporter_vars.yml # Overwrite variables in group_vars (optional)
    ├── hosts
    └── host_vars
        ├── node1.voidquark.com
        │   └── host_vars.yml # Overwrite variables in host_vars (optional)
        └── node2.voidquark.com
            └── host_vars.yml # Overwrite variables in host_vars (optional)

• inventory hosts file example:

[node_exporter]
node1.voidquark.com
node2.voidquark.com

License

MIT

Contribution

Feel free to customize and enhance the role according to your needs. Your feedback and contributions are greatly appreciated. Please open an issue or submit a pull request with any improvements.

Author Information

Created by VoidQuark