Complete Linux Bash Shell Scripting with Real Life Examples

This lab setup guides you through building a Linux lab using Oracle VirtualBox, installing a virtual machine, and preparing a CentOS/Red Hat environment to practice Bash scripting.

Discover Oracle VirtualBox, a free, open source hypervisor for x86 computers that lets you run multiple operating systems on one hardware, including Windows, Mac, and Linux.

Download and install Oracle VirtualBox from virtualbox.org, choose Windows host, accept prompts, and finish the setup wizard. Then launch VirtualBox to create a new Linux virtual machine for lab practice.

Create a Linux virtual machine in VirtualBox, setting 64-bit Linux, allocate memory, create a 10 GB dynamically allocated VDI disk, and enable virtualization in BIOS if needed.

Download the CentOS 7 ISO, create a virtual machine, install CentOS 7 with GUI, and configure root and user accounts via the desktop terminal.

Learn to download the CentOS 8 ISO and install it in Oracle VirtualBox. Explore configuring the GUI server, network settings, hostname, root and user accounts, and completing the first boot.

Create a virtual machine, download the CentOS 9 stream ISO, and install CentOS 9 stream with VirtualBox or VMware Workstation, then configure networking.

Explore shell scripting basics and how the kernel interacts with the shell and hardware. Learn about Korn shell, Bash, and C shell, starting a shell, and running scripts.

Learn how the Linux kernel interfaces hardware and software, receiving commands from the shell and passing them to hardware, forming the operating system.

Explain how a Linux shell serves as the interface between users and the kernel, enabling you to run commands in a terminal or command line interface and inspect your environment.

Discover what a shell script is and how the shell runs commands in sequence, using copy and move operations as examples, on Linux command line.

Explore Linux shells such as bash, sh, csh, tcsh, and korn shell, their features and compatibility, and how to view them with /etc/shells.

Learn to start and switch shells, verify the active shell with echo $0, and check available shells with cat shells, including pwd and ls -l usage in Linux bash scripting.

Learn to run a shell script using absolute and relative paths, including /home/youruser/scripts/xyz-script and ./xyz-script from the current directory.

Explore essential scripting standards, including naming conventions, directory structure, and file permissions, then learn shell script formats, execution order, and variables.

Adopt a clear script naming convention by creating a dedicated scripts directory, naming files by function or date, and using the proper shell extension (bash, korn shell, etc.).

Learn how to assign proper executable permissions to scripts using chmod a+x, understand rwx bits for user, group, and others, and why default files lack execute rights.

Learn proper shell script format by defining the shell, adding informative comments, and formatting variables and commands for readability, with emphasis on indentation and using vi or vim.

Learn how a script executes commands in strict sequence from start to finish, with commands running one, two, three in order, examples include date and cal.

Learn to create your first shell script, handle input and output, define variables, use conditionals and loops, and automate admin tasks like disk space and memory checks.

Create and run your first bash script that outputs hello world, set executable permissions, and run it from both absolute and relative paths while learning basic scripting setup.

Design and run a basic Linux shell script that prints the working directory, lists files, shows user, date, and calendar, and creates three files with touch, sequentially.

Create a script to run basic administration tasks like top, df -h, free -m, uptime, and iostat to check system health and automate routine checks.

Define variables at the start of a bash script and run them with a dollar prefix, using p, l, w, d, c for pwd, ls, whoami, date, and cal.

Learn to build a Bash input/output script using read and echo, prompt for user input, store responses in variables, and display the host name dynamically.

Learn to write bash if-then and if-else scripts, define variables, and test file existence with -e. Build real life examples that run and show outputs.

Explore bash case statements that map user choices to commands like date, ls, who, and uptime, enabling interactive scripts with choices and executable permissions.

Learn how for loop scripts automate repetitive tasks in Linux Bash, iterating over numbers or items to run commands, create multiple files, and manage executable permissions.

Explore do-while scripts in bash that repeat a block while a condition is met, with a countdown example using sleep and echo and exiting at the target time.

Master exit status in bash, where zero indicates success and non-zero codes signal errors, and apply it in shell scripting with echo $?, if statements, and real-world examples.

Explore real life linux bash shell scripting by examining scripts that automate daily tasks in system administration and engineering, with practical real world examples.

Learn to access data from files with bash scripting, filtering log messages for errors, warnings, and failures. Automate data extraction, redirect outputs to files, and format results for admin tasks.

Learn to write bash scripts that check remote server connectivity with ping, using if-else, do-while, variables, loops, and a host file to ping multiple IPs.

Schedule shell scripts with cron jobs to run at set times. Learn to redirect output to files and notify users by email when executions occur.

Create a shell script from scratch to delete or rename files older than 90 days, test with timestamped files, and schedule via cron for automation.

Learn to back up critical Linux directories like /etc and /var with tar and gzip, then automate the process in a script that verifies, archives, and securely transfers the backup.

Explore practical Bash for loops for the file system by counting, creating multiple files with dynamic names, and assigning permissions, with user input and timing demonstrations.

Master for loops to rename txt files and verify file existence on different servers, with practical, real-life bash scripting examples.

Write a bash script to copy files to multiple remote hosts using a for loop and scp. Learn to source hostnames from a file to automate transfers across many servers.

Identify orphaned home directories by matching /home contents against user entries in /etc/passwd, using a test script run as root to report orphans and justify deletions.

Learn to list users logged in by date with bash scripting, using last, date, and grep, and add user input for specific day or month, plus optional cron automation.

Build a central logging workflow that tails /var/log/messages, filters for error keywords, and writes matches to a file; optionally email alerts via a separate script and cron job.

Automate Linux user account creation with five Bash scripts that check for existing users, add descriptions, handle custom user IDs, and combine into a full workflow.

Identify inactive users with lastlog and lastlog -B 90, filter system accounts, then automate disabling with a for loop script or an argument-based script using usermod -L.

Check running processes, identify zombie or orphaned ones, and terminate them with Bash scripting using ps -f, grep, awk, and optional xargs or a for loop.

Master disk space monitoring in Linux using df -h, filtering with grep and awk, and scripting with for, while, or one-liner checks to alert on thresholds.

Learn to build a file-count script that uses ls -l and wc -l to compare against a defined threshold, then notify via email or cron-driven workflows.

Create a system inventory with bash scripts that collect host, IP address, and description, validate entries in a database, and support adding or deleting records via a case statement.

Automate the predefined header information for new bash scripts, including the shebang, author, date, description, and modification fields, by using a meta script that generates executable scripts.

Use online help to improve Linux bash scripting: search precisely with engines like Google, ask questions, compare sources, and document solutions while also helping others.

Celebrate mastering complete linux bash shell scripting with real life examples as you complete the course.

Explore additional resources to deepen your Linux bash shell scripting skills through real-life examples.

Troubleshoot putty connectivity issues to access Linux VM, covering Oracle VirtualBox NIC settings, host-only vs bridged adapters, network interface status, and ensuring SSH daemon runs.

Explore the root account in Linux, the powerful admin who can create, modify, or delete accounts and alter system configuration files; Linux is case sensitive and file names avoid spaces.

Explore the seven Linux file types, regular files, directories, links, device files, sockets, named pipes, and block devices, and how to identify them from the ls -l first column.

Explore how wild cards in Linux use the asterisk, question mark, and brackets to match patterns, create and delete multiple files with brace expansion, and streamline commands.

Discover soft links and hard links in Linux, and how to create them with ln and ln -s, including that soft links vanish with the source while hard links persist.

Learn how Linux assigns file ownership to a user and a group, and how to change ownership with chown and change group with chgrp, including recursive options.

Master tab completion to auto-fill commands, files, and directories, reducing typing and speeding Linux workflows. Use the up arrow (and down arrow) to cycle through and re-run previous commands.

Master combining multiple files into one and splitting large files into smaller chunks with Linux commands, including 300-line splits, for efficient transfer and log file handling.

Learn to use the vi editor to create and edit Linux files, switch between insert and command modes, delete text, save, quit, search, replace, and navigate efficiently.

Explore the sed command for substituting text, deleting lines, removing empty lines, replacing tabs with spaces, and applying global changes, with in-place edits and practical examples.

Master Linux system utility commands such as date, uptime, host name, uname -a, which, pwd, cal, bc, and ls -l, and learn binary locations in /usr/bin.

Discover essential terminal commands like clear, exit, and script to manage your shell sessions, log activity, and troubleshoot by recording every command and output.

Learn to create and use Linux aliases to shorten long commands, chain tasks like pwd and ls, display directories with grep, and safely escape variables while managing and removing aliases.

Configure Linux nic bonding to achieve high availability and throughput by aggregating two nics into bond0 using mode five transmit load balancing, with master and slaves, then restart the network.

Explore essential Linux file transfer commands including FTP, SCP, and rsync, and the use of cron for backups, with practical tips on troubleshooting and daemon status.

Explore raid, the redundant array of independent disks, which provides redundancy and speed across disks, covering raid 0, 1, and 5 and their parity.

Discover facts about information technology, including job growth, salary ranges, outsourcing trends, and pathways through certifications for entering the information technology field.

Compare Red Hat and CentOS 5, 6, and 7, noting Red Hat support versus CentOS community support, and the move from legacy tools to systemctl, yum, and nmcli.

Learn practical Linux hardening techniques to secure accounts, remove unused packages, disable unnecessary services, audit listening ports, and strengthen SSH with firewall and SELinux controls, plus timely updates.

Discover how SELinux, the security-enhanced Linux kernel module, enforces mandatory access control through labeling and type enforcement, and manage its modes, booleans, and policies for secure servers.

Learn to troubleshoot Linux system performance by identifying bottlenecks—cpu, memory, disk, network, hardware—and master key commands like df, du, top, iostat, lsof, tcpdump, and more.

Learn how virtualization uses a hypervisor to run multiple virtual machines on one host. Explore terms like virtual machine, virtual desktop, snapshot, clone, and host across VMware and Hyper-V contexts.

Explore VMware virtualization fundamentals, including ESXi hypervisor, vCenter and vSphere, and how clusters, hosts, and VMs, storage, networking, and monitoring are managed.

Explore the bonus section of the complete Linux Bash shell scripting course, featuring practical tips and real life examples to strengthen your Bash scripting skills.