Why Linux powers the internet in Linux CLI - Why It Works

Introduction

Linux is the operating system that runs most of the internet's servers. It is reliable, secure, and free, which helps websites and services stay online and fast for everyone.

When you want a stable system to host websites that must run 24/7 without crashing

When you need a secure environment to protect user data on your online service

When you want to customize your server to run specific internet applications efficiently

When you want to save costs by using free and open-source software for your servers

When you want to use powerful tools and scripts to automate server management

Commands

This command shows the Linux system information, confirming the server runs Linux.

Terminal

uname -a

Expected Output

Linux my-server 5.15.0-60-generic #66-Ubuntu SMP Fri Feb 17 15:06:34 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

This command shows the current system resource usage, helping to monitor server health.

Terminal

top -b -n 1 | head -n 5

Expected Output

top - 10:00:00 up 10 days,  3:22,  1 user,  load average: 0.00, 0.01, 0.05

Tasks: 120 total,   1 running, 119 sleeping,   0 stopped,   0 zombie

%Cpu(s):  1.0 us,  0.5 sy,  0.0 ni, 98.0 id,  0.5 wa,  0.0 hi,  0.0 si,  0.0 st

KiB Mem :  2048000 total,   500000 free,   800000 used,   748000 buff/cache

KiB Swap:  1024000 total,  1024000 free,        0 used.   900000 avail Mem

→

-b - Run top in batch mode for scripting

→

-n 1 - Show only one iteration of output

This command checks if the Nginx web server is running, which is common on Linux internet servers.

Terminal

ps aux | grep nginx

Expected Output

www-data  1234  0.0  0.1  123456  2345 ?  Ss   09:59   0:00 nginx: master process /usr/sbin/nginx

www-data  1235  0.0  0.2  123456  3456 ?  S    09:59   0:00 nginx: worker process

This command shows disk space usage for the web server directory, important to keep websites running smoothly.

Terminal

df -h /var/www

Expected Output

Filesystem      Size  Used Avail Use% Mounted on

/dev/sda1        50G   20G   28G  42% /var/www

→

-h - Show sizes in human-readable format

Key Concept

If you remember nothing else, remember: Linux is the backbone of internet servers because it is stable, secure, and flexible.

Common Mistakes

Trying to run internet services on unsupported or unstable operating systems

This can cause frequent crashes and downtime, making websites unreliable

Use Linux distributions known for stability and support, like Ubuntu Server or CentOS Stream

Ignoring system resource monitoring commands

Without monitoring, servers can run out of memory or CPU, causing slow or failed services

Regularly use commands like top and df to check server health and disk space

Not verifying if essential services like web servers are running

If the web server is down, websites become inaccessible to users

Use commands like ps aux | grep nginx to confirm services are active

Summary

Use uname -a to confirm the server runs Linux, the common OS for internet servers.

Monitor system health with top and disk space with df to keep services running smoothly.

Check that web servers like Nginx are running to ensure websites stay online.