Why Linux powers the internet in Linux CLI - See It in Action

Why Linux Powers the Internet

📖 Scenario: You are a system administrator learning why Linux is the backbone of the internet. You will explore simple Linux commands and concepts that show Linux's power and flexibility in managing internet services.

🎯 Goal: Build a small script that lists active network connections, filters those related to internet services, and counts them. This will help you understand how Linux manages internet traffic.

📋 What You'll Learn

Use the ss command to list network connections

Create a variable called connections to store the output of ss -tuln

Create a variable called internet_connections to filter lines containing :80 or :443

Count the number of internet connections and store it in count

Print the count with a descriptive message

💡 Why This Matters

🌍 Real World

System administrators use Linux commands and scripts like this to monitor and manage internet services on servers.

💼 Career

Understanding Linux networking commands is essential for roles in IT support, network administration, and cybersecurity.

1

List all active network connections

Create a variable called connections and assign it the output of the command ss -tuln using command substitution.

Linux CLI

# Create a variable called connections with the output of ss -tuln
# Your code here

Need a hint?

Use $(command) to capture command output into a variable.

2

Filter internet service connections

Create a variable called internet_connections that filters connections to include only lines containing :80 or :443 using grep.

Linux CLI

connections=$(ss -tuln)
# Filter connections for :80 or :443 and store in internet_connections
# Your code here

Need a hint?

Use grep -E ':80|:443' to match either port 80 or 443.

3

Count the filtered internet connections

Create a variable called count that counts the number of lines in internet_connections using wc -l.

Linux CLI

connections=$(ss -tuln)
internet_connections=$(echo "$connections" | grep -E ':80|:443')
# Count lines in internet_connections and store in count
# Your code here

Need a hint?

Use wc -l to count lines.

4

Display the count of internet connections

Print the message "Number of active internet connections: " followed by the value of count using echo.

Linux CLI

connections=$(ss -tuln)
internet_connections=$(echo "$connections" | grep -E ':80|:443')
count=$(echo "$internet_connections" | wc -l)
# Print the count with a descriptive message
# Your code here

Need a hint?

Use echo "Number of active internet connections: $count" to print the message.

The actual number may vary; for validation, zero is acceptable if no connections exist.