Linux System Monitoring Guide: Master Resource Management Tools

Effective system monitoring is crucial for maintaining healthy Linux systems. This guide covers essential tools for monitoring system resources.

Table of Contents

Disk Usage Monitoring

Check Filesystem Space

df -h

Output:

$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda1        98G   48G   45G  52% /
/dev/sda2       146G   98G   41G  71% /home

Directory Size Analysis

du -sh */

Memory Management

View Memory Usage

free -m

Output:

$ free -m
              total        used        free      shared  buff/cache   available
Mem:          15951        4589        7855         524        3506       10582
Swap:          2047           0        2047

Interactive Quiz

Question 1

How would you find the top 5 largest directories in /home?

du -h /home | sort -rh | head -n 5

Question 2

What command shows real-time CPU and memory usage?

top
# or
htop

Performance Analysis

CPU Usage

mpstat 1

I/O Statistics

iostat -x 1

Best Practices

1. Regular monitoring schedule
2. Set up alerting thresholds
3. Keep historical data
4. Monitor all critical systems
5. Document baseline performance

Practical Examples

Find Large Files

find / -type f -size +100M -exec ls -lh {} \;

Monitor System Load

watch -n 1 'cat /proc/loadavg'

Complete System Analysis Script

#!/bin/bash
echo "=== System Resources Overview ==="
date
echo -e "\n=== Disk Usage ==="
df -h
echo -e "\n=== Memory Usage ==="
free -m
echo -e "\n=== CPU Load ==="
uptime
echo -e "\n=== Most Memory Intensive Processes ==="
ps aux --sort=-%mem | head -n 5

Common Monitoring Scenarios

1. High CPU Usage

top -b -n 1 | head -n 12

2. Disk Space Issues

df -h | awk '{ if($5 > "80") print $0 }'

3. Memory Problems

vmstat 1 5

Conclusion

Effective system monitoring is essential for maintaining reliable Linux systems. Regular monitoring and proactive management help prevent system issues.

Quick Reference Guide

Complete Linux Command Line Series

1. Find Command Guide
2. Process Management
3. Text Processing
4. Network Commands
5. System Monitoring (Current Article)

Additional Resources

• Linux Performance Tuning Guide
• Advanced System Administration
• Automation with Shell Scripting
• Container Monitoring