Node Exporter is a monitoring agent designed to gather system-level metrics such as CPU, memory, disk, and network usage, exposing them for Prometheus to collect and analyze.

Prometheus serves as a powerful monitoring solution that relies on exporters like Node Exporter to fetch data from various systems.

Installing Rocky Linux

Refer to the following resources for setting up Rocky Linux:

• VMware Workstation installation guide (with license key)
• Creating a virtual machine using VMware Workstation
• Downloading and installing Rocky Linux
• Setting a static IP address for the network enterface
• Installing MobaXterm for remote access

Deploying Node Exporter on Rocky Linux

1. Download Node Exporter

   Visit the official Prometheus download page at https://prometheus.io/download/ and select the Linux amd64 version of the latest release.

2. Transfer the Package

   Upload the downloaded archive to the root directory (/root/) using SFTP.

   [root@localhost ~]# ll /root/
   

3. Extract and Move

   Extract the package into /opt/:

   [root@localhost ~]# tar zxvf /root/node_exporter-1.7.0.linux-amd64.tar.gz -C /opt/
   

   Then rename the extracted folder:

   [root@localhost ~]# mv /opt/node_exporter-1.7.0.linux-amd64/ /opt/node_exporter
   

4. Create Systemd Service

   Define a service file for automatic startup:

   [Unit]
   Description=Node Exporter
   After=network.target
   
   [Service]
   Type=simple
   ExecStart=/opt/node_exporter/node_exporter \
     --collector.ntp \
     --collector.mountstats \
     --collector.systemd \
     --collector.tcpstat
   User=prometheus
   ExecReload=/bin/kill -HUP $MAINPID
   Restart=on-failure
   
   [Install]
   WantedBy=multi-user.target
   

   Save it as /etc/systemd/system/node_exporter.service.

5. Set Permissions

   Adjust ownership of the directory:

   [root@localhost ~]# chown prometheus:root -R /opt/node_exporter
   

6. Reload Services and Enable Startup

   Reload systemd configuraton and enable the service:

   [root@localhost ~]# systemctl daemon-reload
   [root@localhost ~]# systemctl enable node_exporter.service
   

7. Start and Verify

   Launch the service and check its status:

   [root@localhost ~]# systemctl start node_exporter.service
   [root@localhost ~]# systemctl status node_exporter.service
   

8. Configure Firewall

   Open port 9100 for external access:

   [root@localhost ~]# firewall-cmd --zone=public --add-port=9100/tcp --permanent
   [root@localhost ~]# firewall-cmd --reload
   

9. Validate Metrics Endpoint

   Access http://<your-host>:9100/metrics to confirm data availability.

10. Update Prometheus Configuration

    Add the target to Prometheus's configuration file (/opt/prometheus/prometheus.yml):

    - job_name: 'nodes'
      static_configs:
        - targets: ['192.168.100.10:9100']
    

11. Restart Prometheus

    Apply changes by restarting Prometheus:

    [root@localhost ~]# systemctl restart prometheus.service
    [root@localhost ~]# systemctl status prometheus.service
    

12. Verify Target Status in Prometheus UI

    Navigate to http://<prometheus-host>:9090, go to "Status" → "Targets" to verify that the Node Exporter is correctly registered.