Bash Scripting on Linux (The Complete Guide) Class 01 - Course Introduction

Summary

Welcome to the Bash scripting course on Learn Linux TV, where you'll learn to automate repetitive tasks and harness the power of bash, a versatile command interpreter akin to a programming language. Instructor Jay, with over 20 years of Linux experience, guides you through foundational concepts to advanced scripting, covering variables, loops, conditionals, and more. Each episode is available for a comprehensive learning experience, aiming to turn you into a proficient bash scripter.

Takeaways

• 📝 The course is designed to teach everything needed to write bash scripts for Linux administrators and DevOps professionals.
• 🔄 Bash scripting automates the execution of repeated commands, saving time and effort.
• 🛠 Bash offers advanced features like if statements, while loops, and variables, making it almost a programming language.
• 📚 The instructor, Jay, has over two decades of experience with Linux and scripting, and is the owner of Learn Linux TV.
• 📘 Jay has written books, including 'Mastering Ubuntu Server', which can be found at www.ubuntuserverbook.com.
• 🎥 The entire series of videos is available on YouTube for viewers to learn at their own pace.
• 🔢 The course will cover foundational concepts like variables and math functions in bash, which are essential for scripting.
• 🔐 The course will also delve into conditional statements, exit codes, loops, and other scripting constructs.
• 📁 The importance of knowing where to save scripts on the Linux file system will be discussed to ensure easy access and organization.
• 🔁 The course will explore data streams and functions to control data flow and script behavior.
• 🗓️ Scheduling jobs and understanding arguments for scripts will be covered to enhance script utility and flexibility.

Q & A

What is the main purpose of writing bash scripts according to the video?

The main purpose of writing bash scripts is to automate the execution of a series of commands that are run repeatedly, thus saving time and effort for Linux administrators or DevOps professionals.

Why might someone consider bash scripting similar to a programming language?

Bash scripting might be considered similar to a programming language because it offers features like if statements, while loops, and the ability to use variables, which are common in programming languages.

What does the instructor claim about the episodes of the bash scripting course?

The instructor claims that every single episode of the bash scripting course is already uploaded on YouTube, allowing viewers to watch them all at once or take their time learning the concepts.

What is Jay's professional background, and how does it relate to the course?

Jay is the owner of Learn Linux TV, an education company specializing in Linux. He has over two decades of experience with Linux and has held various positions in system administration, network administration, DevOps management, and other roles. His extensive background in Linux makes him well-suited to teach the course.

What is the significance of the 'hello world' script in the context of the course?

The 'hello world' script is significant as it is traditionally the first example taught in programming and scripting languages, and the course follows this tradition by starting with it.

Why are variables covered early in the course?

Variables are covered early in the course because they are a foundational concept in scripting, and they will be used in many of the lessons throughout the course.

What is the role of exit codes in bash scripting?

Exit codes in bash scripting indicate whether a command or script was successful. They help administrators understand the result of a script and take appropriate action based on that result.

What is the purpose of while loops in the course?

While loops are used in the course to teach how to write scripts that monitor for a file or other criteria to decide whether the script should continue running or exit, providing control over script execution.

What does the update script example in the course demonstrate?

The update script example demonstrates how to keep servers up to date and serves as a recurring example in several videos throughout the course.

What is the focus of the class on scheduling jobs?

The focus of the class on scheduling jobs is to teach how to schedule tasks to run at specific times or under certain conditions, which is a two-part class in the course.

What additional resources does the instructor offer for further learning?

The instructor offers his latest book, 'Mastering Ubuntu Server', as an additional resource for further learning, which can be found at www.ubuntuserverbook.com or by searching for the book on Amazon.

What are the technical requirements to follow along with the course?

The technical requirements to follow along with the course include having a computer with a terminal and access to a Linux server or a Linux installation, which can be a virtual machine, a spare server, or even a personal computer running Linux.

Outlines

00:00

📚 Introduction to Bash Scripting Course

In this introductory paragraph, the speaker welcomes viewers to the Learn Linux TV course on Bash scripting. The purpose of the course is to teach the essentials of writing Bash scripts, which are useful for automating repetitive command sequences in Linux administration and DevOps roles. The speaker emphasizes the efficiency of scripting over manual command execution and introduces the concept of Bash as a programming language with features like if statements and loops. The course content is outlined, promising to take viewers from basics to advanced scripting, with all episodes available for immediate viewing. The speaker also introduces himself as Jay, an experienced Linux professional and owner of Learn Linux TV, and mentions his book 'Mastering Ubuntu Server'.

05:01

🔍 Course Content and Prerequisites

This paragraph delves into the specifics of the course content, starting with the creation of a 'Hello, World' script, a traditional first step in programming and scripting education. The course will cover foundational topics like variables, math functions, and control structures such as if statements and loops. It will also explore exit codes, data streams, functions, and case statements, leading up to creating a practical backup script. The speaker outlines the lessons, emphasizing the importance of understanding where to save scripts and how to pass arguments to them. The course concludes with a look at job scheduling and资源整合. The paragraph concludes with the prerequisites for the course, which include a computer with terminal access and a Linux installation, suggesting that viewers can use the channel's resources to set up Linux if needed.

10:02

🚀 Getting Started with Bash Scripting

The final paragraph serves as a call to action, encouraging viewers to begin their journey in learning Bash scripting. The speaker reiterates the availability of all course videos for immediate viewing and invites viewers to proceed to the next episode. The paragraph wraps up with a thank you note to the viewers and an expression of enthusiasm for teaching the upcoming lessons. The speaker also hints at the wealth of Linux-related content available on the channel, positioning it as a valuable resource for those new to Linux or needing assistance with installation.

Keywords

💡Bash

Bash, short for 'Bourne Again SHell', is a Unix shell and command language that allows users to interact with the operating system. In the context of this video, Bash is presented as a scripting language for automating tasks on Linux systems. The script is a series of commands saved in a text file that can be executed as a single entity, which is central to the theme of the video.

💡Scripting

Scripting refers to the process of writing scripts, which are sequences of instructions that automate tasks. In the video, the instructor emphasizes the importance of scripting for Linux administrators and DevOps professionals to automate repetitive tasks, thus enhancing efficiency and reducing manual labor.

💡Automation

Automation is the use of control systems to operate equipment such as machinery, processes in a factory, or more broadly, the creation of a process that functions with minimal human intervention. The video discusses the automation of command execution as a key benefit of using Bash scripts, eliminating the need to manually run the same set of commands repeatedly.

💡Linux Administrator

A Linux Administrator is a professional who manages Linux servers and systems. They are responsible for maintaining the stability, performance, and security of the servers. In the script, the instructor addresses Linux administrators as the primary audience for the course, indicating that scripting skills are essential for their role.

💡DevOps

DevOps is a set of practices that combines software development (Dev) and IT operations (Ops) to shorten the system development lifecycle and provide continuous delivery of high-quality software. The video mentions DevOps professionals as the target audience, suggesting that Bash scripting is a valuable skill in the DevOps toolkit.

💡Variables

In programming and scripting, variables are used to store data that can be used or manipulated within a script. The video explains that variables are a foundational concept in Bash scripting, allowing scripts to adapt to different conditions by using stored information.

💡If Statements

If statements are conditional expressions that allow scripts to execute different blocks of code based on whether a certain condition is true or false. The video introduces if statements as a way to introduce branching in scripts, enabling decision-making within the script's execution.

💡Loops

Loops are programming structures that repeat a block of code until a specified condition is met. The video mentions 'while loops' as a feature in Bash scripting that allows scripts to continuously check for certain conditions, such as the presence of a file, before deciding to continue or exit.

💡Exit Codes

Exit codes are values returned by a command or script to indicate its success or failure. In the video, the instructor explains the importance of exit codes for administrators to understand the result of a script or command execution, which is crucial for troubleshooting and automation.

💡Functions

Functions in scripting are reusable blocks of code that perform a specific task. The video mentions functions as a part of the course, suggesting that they are an important concept for creating modular and organized scripts in Bash.

💡Scheduling Jobs

Scheduling jobs refers to the automation of tasks that are set to run at specified times or under certain conditions. The video includes a class on scheduling jobs, indicating that this is a key aspect of Bash scripting for automating routine tasks on Linux systems.

💡Arguments

Arguments in scripting are values passed to a script when it is executed, allowing the script to be dynamic and adaptable to different inputs. The video discusses how to pass arguments to a script, which is essential for creating flexible and reusable scripts.

💡Backup Script

A backup script is a specific type of script designed to create copies of data for the purpose of recovery in case of data loss. The video mentions creating a backup script as a culmination of the course, integrating various concepts learned throughout the series to create a practical tool for server backup.

Highlights

Introduction to a new bash scripting course aimed at teaching everything needed to write bash scripts.

Rationale for writing bash scripts: automating repetitive command execution for efficiency.

Bash scripting's capabilities beyond simple command execution, including conditionals and loops.

Bash's role as a command interpreter or shell with programming language-like features.

Course structure includes an overview and subsequent deep dives into specific bash scripting topics.

Availability of the entire course series on YouTube for self-paced or binge-watching learning.

Instructor Jay's introduction, sharing his extensive experience with Linux and scripting.

Jay's professional background in system administration, network administration, and devops management.

Jay's passion for creating educational content and his latest book 'Mastering Ubuntu Server'.

Course outline detailing the topics covered in each class, starting with a 'Hello, World' script.

Importance of understanding variables as a foundational concept in scripting.

Exploration of math functions in bash and their unique handling compared to other languages.

Introduction to if statements and branching in scripts for decision-making capabilities.

Understanding exit codes as indicators of script or command success.

Utilization of while loops for scripts that monitor conditions to determine execution flow.

Creating an update script as a recurring example to demonstrate scripting concepts.

For loops as a tool for iterating over sequences in bash scripts.

Discussion on where to save scripts in the Linux filesystem for easy access and organization.

Data streams' role in controlling the flow of data within scripts.

Functions in bash scripting for modular and reusable code segments.

Case statements for creating user-selectable menus within scripts.

Scheduling jobs as a two-part class on automating script execution at specified times.

Using arguments to pass information to scripts for dynamic execution.

Creating a comprehensive backup script integrating various course concepts.

Course conclusion with additional resources for further learning and script development.

Prerequisites for the course, including a computer with terminal access and a Linux installation.

Recommendation to use the instructor's YouTube channel for additional Linux installation guidance.

Transcripts

thank you

hello and welcome back to learn Linux TV

and also welcome to my brand new bash

scripting course in this series what I'm

going to do is teach you everything that

you need to know in order to get up and

running when it comes to writing bash

scripts but you might be thinking why

exactly would I want to write a bash

script

well we as Linux administrators or

devops professionals are going to be

running quite a few commands and

eventually we're going to run into a

situation where we have a series of

commands that we need to run every now

and then but if we're going to be

running the same set of commands over

and over again then why not automate it

why would we want to manually run those

commands every time we go to complete

that task

and that's where bash scripting comes in

at its lowest form bash scripting is

just a way to have a bunch of commands

run one after another commands that you

save in a text file and then execute as

a script but that's not all that you

could do in bash bash has all kinds of

cool features such as if statements

while Loops the ability to have

variables and if I didn't know any

better I would say based on that

description it almost sounds like bash

is a programming language well if you're

thinking about bash in terms of a

programming language you're not actually

far off now to be fair bash is actually

a command interpreter or a shell that we

use on our Linux or Unix systems but

don't let the term interpreter fool you

bash is basically a programming language

and the scripts that you could write

within bash are really awesome and

you're going to see examples of that in

this series so what I'm going to do in

this video is introduce the course and

tell you all about it and then in each

video from here on out we're going to

learn more and more about bash scripting

and by the end of this series you're

going to be a pro when it comes to

writing bash scripts and I can't wait to

teach you guys about bash scripting this

is going to be a ton of fun in fact

every single episode in this series is

already on YouTube right now that's

right every single episode has been

uploaded at the exact same time if you

want to binge watch this series you can

go right ahead and do so but then again

it might be better to slow it down a bit

and take your time and make sure that

you're learning all of the concepts

either way every video in this series is

going to be right there waiting for you

whenever you're ready for it anyway like

I mentioned earlier in this video what

I'm going to do is introduce the course

so let's go ahead and switch gears and

I'll give you an overview of what you'll

expect to find in this course

[Music]

so at this point I'll tell you guys a

little bit more about myself

first of all my name is Jay nice to meet

you

now I've been working with Linux for

over two decades it's literally my

favorite technology and writing scripts

has definitely helped me along my career

and I'm sure it'll help you and yours as

well

now professionally I am the owner of

learn Linux TV an education company that

specializes in Linux

before learn Linux TV became my only gig

I've held positions in system

administration Network Administration

devops Management and other roles as

well I Love Leading people leading teams

and I also love technology so my career

has been very good to me in addition to

creating educational videos I also write

books as well my latest book as of the

time I'm recording the series is

mastering Ubuntu Server if you want to

check it out you could go to

www.ubuntuserverbook.com and that domain

will actually take you to whatever the

current version of that book happens to

be at any one time now before you

actually visit that domain I want to

point out that what it'll do is take you

to the United States store for the book

on Amazon and if you live in a different

country then what you'll want to do

instead is go to amazon.com and search

for mastering Ubuntu Server you can do

that on your version of Amazon for your

country and once you do that you should

be able to order the book from an Amazon

site that is closer to your geographic

location anyway I love Linux it's my

favorite technology and I love creating

educational content around Linux so you

know what I couldn't possibly be in a

better place when it comes to my career

because I'm doing what I love I love

teaching I love technology okay so it

all works out

now let's go ahead and take a look at

the outline for this course

the first class will serve as the

introduction and welcome and I would

love to tell you what we're going to do

in that class but we're already doing it

you are actually watching that video

right now

in the next video what we're going to do

is write our very first bash script and

specifically we will create a hello

world script and that's because in well

pretty much any programming language as

well as scripting languages the hello

world example is usually the first thing

that instructors teach you and I am not

going to break that tradition in the

series

in class number three we are going to

explore variables variables allow us to

well save information for later

in addition we could use variables to

make our scripts change depending on

what variables equal and the reason why

we're going to cover variables early in

this course is because it's a very

important foundational concept we will

be using variables in quite a few of the

lessons so it's a good idea to get that

out of the way early in the course class

number four we're going to take a look

at math functions for example how do you

add subtract or multiply numbers in bash

now you might already be familiar with

how to perform math functions in a

programming language perhaps another

scripting language however math

functions are actually a bit different

in bash so we definitely want to make

sure that we take a look at that

continuing in class number five we're

going to take a look at if statements

and that'll also be our first look at

branching basically we can have a script

that does something different depending

on some other criteria a test case if

you will and that allows us to make

decisions within scripts and that's

definitely an important aspect to cover

and continuing on from there in class

number six what we'll do is take a look

at Exit codes

every command and every script is going

to have an exit code and that helps you

as the administrator understand if a

script or command was successful and

knowing that will help you take action

based on the result

class number seven is all about while

loops and that helps us write scripts

that are watching for a file or some

other criteria to understand whether or

not that script should be running or if

it should exit we have full control over

that so that's what we'll explore in

class number seven

in class number eight we're going to

take a little break from branching and

take our first look at an update script

and that particular script is going to

serve as an example in several videos

going forward so that's the first time

that we'll take a look at that and that

update script will help us keep our

servers up to date

in class number nine we will return to

branching this time taking a look at for

Loops in class number 10 we will answer

the question where should I save my

scripts and the reason that question

even comes up is because there's quite a

few directories in the Linux file system

and although we don't need to understand

the purpose of every directory on the

Linux file system it is important to

understand which directories actually

pertain to scripts and that'll help us

answer where we should save our scripts

for later use

continuing into class number 11 we'll

take a look at data streams basically

standard input standard output as well

as standard error data streams

themselves allow us to control the flow

of data in our scripts and that gives us

even more options

in class 12 we'll take a look at

functions and that one's going to be a

lot of fun

class number 13 is all about case

statements and this essentially allows

us to create a menu from which the user

can actually select an option and then

the script responds accordingly

in class number 14 we take our first

look at scheduling jobs so this class is

part one of a two-part class that goes

over exactly that

in class 15 we continue our look at

scheduling jobs

in 16 we'll take a look at arguments

specifically how to pass arguments to a

script and in class number 17 that's

where a majority of what we've learned

in this course will all come together

because we will use quite a few of the

concepts when we create a backup script

and that backup script is going to be

something that you can actually use to

back up your servers and after we do

that class number 18 is going to be our

closing that's where we'll wrap

everything up and I will also give you

some additional resources that you can

use to extend your knowledge even

further

foreign

to get started and I hope you are we're

going to have a lot of fun but you might

be wondering what exactly do I need in

order to follow along with this course

well the first thing you're going to

need is a computer obviously you can't

really write bash scripts on a toaster

actually I probably need to walk that

statement back considering that iot

devices often run Linux and they

probably run scripts too so if you have

an iot toaster well it could probably

run bash scripts but in this course what

we're going to do is just use a computer

and you'll also need a terminal as well

in Windows it's built in in Mac OS it's

built in and also on Linux distributions

it's built in so regardless of what kind

of computer that you have you should be

in good shape in addition to that what

you'll need is a Linux server or some

kind of Linux installation that you

could log into so what you can do for

that is spin up Linux in a virtual

machine maybe a spare server or maybe

even your desktop or laptop if that

already runs Linux then well you have

everything you need but that's about it

if you have a computer and you have the

ability to to spin up a Linux

installation you should be good to go

but if you don't actually have a Linux

installation all set up and you have no

idea how to get one set up do I have the

YouTube channel for you in fact you're

watching it right now the last time I

checked there was almost a thousand

videos on this channel and I'm probably

over that at this time so there's going

to be no shortage of content on this

channel that you can use to get up and

running with Linux in fact you can check

out any of the videos that I already

have that tell you how to install Linux

and you should be good to go anyway I

can't wait to get started and teach you

guys bash scripting this course is going

to be a ton of fun so this is the end of

this particular video right here but

like I mentioned earlier every video in

this series is already on this channel

so you can watch the next episode

anytime you'd like to do so in fact why

don't you go ahead and meet me there

right now in the meantime thank you guys

for watching this particular video and

I'll see you in the next video

[Music]

thank you

[Music]