Monitor CPU, RAM and disk

Monitoring your VPS resources helps you identify bottlenecks, plan upgrades and detect anomalies before they cause downtime.

Quick overview with htop

Install and run htop for an interactive process viewer:

sudo apt install htop -y
htop

htop shows CPU usage per core, memory usage, swap, load average and running processes. Press q to exit.

Memory usage

free -h

Shows total, used, free, shared, buffer/cache and available memory.

Disk usage

# Overall disk usage
df -h

# Directory sizes
du -sh /var/log
du -sh /home/*

# Find largest files
sudo find / -type f -size +100M -exec ls -lh {} \;

CPU information

# Number of cores
nproc

# Detailed CPU info
lscpu

# Current load average
uptime

I/O monitoring with iotop

sudo apt install iotop -y
sudo iotop

Shows which processes are reading/writing to disk.

Network monitoring

# Bandwidth per interface
sudo apt install iftop -y
sudo iftop

# Connection statistics
ss -tuln

Continuous monitoring with vmstat

vmstat 5  # Update every 5 seconds

Set up alerts (optional)

Create a simple script to alert on high usage:

#!/bin/bash
CPU=$(top -bn1 | grep 'Cpu(s)' | awk '{print $2}')
MEM=$(free | grep Mem | awk '{printf "%.0f", $3/$2 * 100}')
DISK=$(df / | tail -1 | awk '{print $5}' | tr -d '%')

echo "CPU: ${CPU}% | RAM: ${MEM}% | Disk: ${DISK}%"

Tip

For production VPS on Baires Host, consider setting up Prometheus + Grafana or Netdata for continuous monitoring with dashboards and alerting.