How to Monitor Server with Prometheus

Prerequisites

Before installing Prometheus, make sure you have:

• SSH access to your VPS
• Root or sudo privileges
• At least 2GB RAM (for Prometheus)

Step 1: Install Node Exporter (Collects metrics)

Connect to your VPS:

ssh hxroot@YOUR_SERVER_IP -p 22

wget https://github.com/prometheus/node_exporter/releases/download/v1.6.0/node_exporter-1.6.0.linux-amd64.tar.gz
tar xvf node_exporter-1.6.0.linux-amd64.tar.gz
sudo mv node_exporter-1.6.0.linux-amd64/node_exporter /usr/local/bin/
rm -rf node_exporter-1.6.0.linux-amd64*

Create systemd service:

sudo nano /etc/systemd/system/node_exporter.service

Add:

[Unit]
Description=Node Exporter
After=network.target

[Service]
Type=simple
User=nobody
ExecStart=/usr/local/bin/node_exporter

[Install]
WantedBy=multi-user.target

Start and enable:

sudo systemctl daemon-reload
sudo systemctl start node_exporter
sudo systemctl enable node_exporter

Verify (port 9100):

curl http://localhost:9100/metrics

Step 2: Install Prometheus

wget https://github.com/prometheus/prometheus/releases/download/v2.47.0/prometheus-2.47.0.linux-amd64.tar.gz
tar xvf prometheus-2.47.0.linux-amd64.tar.gz
sudo mv prometheus-2.47.0.linux-amd64 /opt/prometheus

Create config:

sudo nano /opt/prometheus/prometheus.yml

Add:

global:
  scrape_interval: 15s

scrape_configs:
  - job_name: 'node'
    static_configs:
      - targets: ['localhost:9100']

Create systemd service:

sudo nano /etc/systemd/system/prometheus.service

Add:

[Unit]
Description=Prometheus
After=network.target

[Service]
Type=simple
User=nobody
ExecStart=/opt/prometheus/prometheus --config.file=/opt/prometheus/prometheus.yml --storage.tsdb.path=/opt/prometheus/data

[Install]
WantedBy=multi-user.target

Start and enable:

sudo systemctl daemon-reload
sudo systemctl start prometheus
sudo systemctl enable prometheus

Allow firewall (port 9090):

sudo ufw allow 9090/tcp

Step 3: Access Prometheus Dashboard

Open browser:

http://YOUR_VPS_IP:9090

You can query metrics like node_cpu_seconds_total.

Step 4: Install Grafana (Optional, for beautiful dashboards)

sudo apt install -y software-properties-common
sudo add-apt-repository "deb https://packages.grafana.com/oss/deb stable main"
wget -q -O - https://packages.grafana.com/gpg.key | sudo apt-key add -
sudo apt update
sudo apt install grafana -y
sudo systemctl start grafana-server
sudo systemctl enable grafana-server
sudo ufw allow 3000/tcp

Access Grafana at http://YOUR_VPS_IP:3000 (default admin/admin).

Add Prometheus as data source (URL: http://localhost:9090).

Import dashboard ID 1860 for Node Exporter.