Showing posts with label Linux Training: Day-2. Show all posts
Showing posts with label Linux Training: Day-2. Show all posts

Day 2: Linux Commands & Network Configuration

Welcome to Day 2 of Linux Training 🚀

In Day 1, we learned Linux fundamentals, installation, and boot process.
Today, we dive into the most important part of Linux administration — Command Line Operations and Network Configuration.

Mastering commands is essential for every:

  • Linux Administrator

  • DevOps Engineer

  • Cloud Engineer

  • System Engineer


📋 Agenda – Day 2

  • Introduction to Linux Commands

  • File Management Commands

  • Process Management Commands

  • System Administration Commands

  • Network Commands

  • Network Configuration (RedHat, Ubuntu, Azure)

  • Network Configuration using NMTUI


🖥 Introduction to Linux Command Line

The Linux Command Line Interface (CLI) allows users to interact directly with the operating system.

Why CLI is important?

✔ Faster than GUI
✔ Required for servers
✔ Enables automation
✔ Essential for troubleshooting
✔ Used in cloud & DevOps environments


📂 File Management Commands

📁 Directory Commands

ls        # List files and directories
cd        # Change directory
pwd       # Show current path
mkdir     # Create directory
rmdir     # Remove directory

📄 File Operations

touch     # Create file
cp        # Copy file/directory
mv        # Move or rename
rm        # Remove file

🔍 Viewing & Searching Files

cat       # View file
vi        # Edit file
head      # First 10 lines
tail      # Last 10 lines
more      # Page view
less      # Scroll view
find      # Search files
grep      # Search text

📦 Compression Commands

tar
zip
unzip
bzip2
bunzip2

🔗 Links & Redirection

ln        # Create links
>         # Overwrite output
>>        # Append output

⚙ System Administration Commands

sudo
su
date
uptime
reboot
shutdown
uname
hostname
history
last
dmesg
dmidecode
systemctl

Example:

systemctl status sshd
systemctl start httpd
systemctl enable httpd

🔄 Process Management Commands

ps
top
kill
lsof
fuser -cu

Example:

kill -9 <PID>

🌐 Network Commands

ping
ip addr
netstat
ss
ssh
scp
rsync
tracepath
hostname -I

🌍 Network Configuration in RedHat / Rocky Linux (Manual Method)

Edit configuration file:

vi /etc/sysconfig/network-scripts/ifcfg-eth0

Example configuration:

DEVICE=eth0
BOOTPROTO=static
ONBOOT=yes
IPADDR=192.168.1.100
NETMASK=255.255.255.0
GATEWAY=192.168.1.1
DNS1=8.8.8.8

Restart network:

systemctl restart network

🌍 Network Configuration in Ubuntu (Netplan)

Edit file:

vi /etc/netplan/50-cloud-init.yaml

Example:

network:
  ethernets:
    ens160:
      addresses:
        - 192.168.2.223/24
      gateway4: 192.168.2.1
      nameservers:
        addresses:
          - 192.168.2.1
  version: 2

Apply configuration:

netplan apply

🌐 Network Configuration Using NMTUI (Interactive Method)

Apart from manual configuration, Linux provides an interactive tool called nmtui (Network Manager Text User Interface).

This method is easier and reduces configuration mistakes.


🚀 Open NMTUI

nmtui

You will see options:

  • Edit a connection

  • Activate a connection

  • Set system hostname


📝 Configure Static IP Using NMTUI

Step 1: Edit Connection

  • Select Edit a connection

  • Choose your interface (example: ens160)

  • Click Edit

Step 2: Change IPv4 Configuration

  • Change from Automatic (DHCP)Manual

  • Add:

    • IP Address

    • Gateway

    • DNS Server

  • Enable:
    ✔ Automatically connect
    ✔ Available to all users

Save the configuration.


Step 3: Activate Connection

  • Go to Activate a connection

  • Deactivate and Reactivate the interface


🔄 Restart NetworkManager (If Needed)

systemctl restart NetworkManager

🔍 Verify IP Address

ip addr

or

nmcli device show

☁ Network Configuration in Azure Cloud

Steps:

  1. Login to Azure Portal

  2. Open Virtual Machine

  3. Go to Networking

  4. Select Network Interface

  5. Change IP Assignment → Static

  6. Save changes


📌 Day 2 Conclusion

Today we covered:

✔ Linux Command Basics
✔ File Management
✔ Process Management
✔ System Administration Commands
✔ Network Commands
✔ Static IP Configuration (Manual + Netplan)
✔ Network Configuration using NMTUI
✔ Azure Network Setup