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Reddit mentions of The Linux Command Line: A Complete Introduction
Sentiment score: 30
Reddit mentions: 49
We found 49 Reddit mentions of The Linux Command Line: A Complete Introduction. Here are the top ones.
or
- No Starch Press
Features:
Specs:
| Height | 11 Inches |
| Length | 8.5 Inches |
| Number of items | 1 |
| Release date | January 2012 |
| Weight | 2 Pounds |
| Width | 1.09 Inches |
Okay. It was /u/iconrad. Here is the thread:
https://www.reddit.com/r/linuxadmin/comments/2s924h/how_did_you_get_your_start/cnnw1ma
Also, I highly, highly recommend buying "The linux command line". Its a book aimed at beginners that will teach you the why, what and how of linux like no other. Its also free on the authors site in true libre fashion.
Sorry for getting all dramatic, but for me you're asking a red pill/blue pill question. I applaud your curiosity and can only recommend you follow your gut and take the red pill. The truth is by asking the question you already know what to do next. Just keep going. However I'll give you a few ideas because you got me excited.
OSX Terminal
Underneath the shiny GUI surface of your mac you have an incredible unix style OS just waiting to be played with and mastered. A few tips to get you going.
Download iTerm 2. Press cmd-return, cmd-d and command-shift-d.
Congrats. you now have a hollywood hacker style computer
Copy and paste this line into your terminal and say yes to xcode.
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
Awesome you now have homebrew. A linux style package manager.
May as well get cask too.
brew install caskroom/cask/brew-cask
Now you can install programs by typing a couple of words.
try
brew cask install virtualbox
Get Linux ASAP
Linux is relatively easy to get up and running and awesome fun. try any of these options
If any of the above seems slightly daunting don't sweat it. Be confident and you may just surprise yourself at how much you can learn in such a short amount of time.
Learn the command line
The command line opens up the wonderfully powerful and creative world of unix. Push on.
Play, Play, Play
Do what gets you excited.
I got a big kick out of learning ssh and then pranking my friends with commands like
say hello friend, i am your computer. i think your friend two-gun is very handsome. Is he single?
or
open -a "Google Chrome" https://www.youtube.com/watch?v=X0uYvQ_aXKw
Do what you find fun. Oh and check out Richard Stallman. He's a good egg.
Enjoy.
edit-0
forgot iTerm link
edit-1
Wow! Gold! Ha! Thank you. This is so unexpected! I'd like to thank the academy, my agent, my mom...
Here is a "curriculum" of sorts I would suggest, as it's fairly close to how I learned:
Generally you'll probably want to look into IA-32 and the best starting point is the Intel Architecture manual itself, the .pdf can be found here (pdf link).
Because of the depth of that .pdf I would suggest using it mainly as a reference guide while studying "Computer Systems: A Programmers Perspective" and "Secrets of Reverse Engineering".
Of course if you just want to do "pentesting/vuln assessment" in which you rely more on toolsets (for example, Nmap>Nessus>Metasploit) structured around a methodology/framework than you may want to look into one of the PACKT books on Kali or backtrack, get familiar with the tools you will use such as Nmap and Wireshark, and learn basic Networking (a simple CompTIA Networking+ book will be a good enough start). I personally did not go this route nor would I recommend it as it generally shys away from the foundations and seems to me to be settling for becoming comfortable with tools that abstract you from the real "meat" of exploitation and all the things that make NetSec great, fun and challenging in the first place. But everyone is different and it's really more of a personal choice. (By the way, I'm not suggesting this is "lame" or anything, it was just not for me.)
*edited a name out
2nd this.
The Linux Command Line. Author offers free PDF for download or you can support and buy from amazon.
http://linuxcommand.org/tlcl.php
 
https://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894/r
Tanenbaum's textbook is par for the course THE best low-level exploration of the fundamental concepts of operating systems. It is, however, HIGHLY theoretical, and requires a solid base of knowledge prior to even starting it. It also is not useful for learning specifics about every day tasks.
This is a phenomenal introduction to the concepts and some of the practice of Linux:
http://www.amazon.com/How-Linux-Works-Superuser-Should/dp/1593275676/ref=sr_1_1?ie=UTF8&qid=1454103950&sr=8-1&keywords=how+linux+works
And here is a practical-first exploration of how to use Linux:
http://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894/ref=sr_1_3?ie=UTF8&qid=1454103950&sr=8-3&keywords=how+linux+works
I would highly recommended reading these two books, then picking up a copy of Tanenbaum's, and finally this:
http://www.amazon.com/s/ref=nb_sb_ss_i_2_9?url=search-alias%3Daps&field-keywords=unix+and+linux+system+administration+handbook&sprefix=linux+sys%2Caps%2C204&rh=i%3Aaps%2Ck%3Aunix+and+linux+system+administration+handbook
If you actually study and practice implementing the topics discussed in these four books then you will have a far better understanding than 90% of the Linux users I've interacted with.
the easiest way is to strictly identify which part is really the variable:
foo=test
cp $foofile testdir/. # cp: missing destination file operand after 'testdir/.' ($foofile doesn't exist and expanded to null, not enough required params for cp)
cp "$foofile" testdir/. # cp: cannot stat '': No such file or directory ($foofile still doesn't exist, but expanded to '' due to double quotes usage - good practice)
cp ${foo}file testdir/. # will compy 'testfile' if exists
Also it is usefull to access command line params from inside the script if there are more than 9 params, to access 10th param use ${10}
and here is some list i noticed for myself of how to use this braces, while reading this book - would recommend:
Sorry for formating issues, reddit treats spaces and new lines in special way..
variable substitution:
substitution:
Bash supports various variables substitutions:
$a - will be substituted with 'a' value
${a} - same as $a but could be concatenated w/ string w/o spaces:
${a}.txt - will be expanded in a_value.txt
${11} - 11th positional parameter given to script from shell
${var:-word} - if 'variable' is set, the result will be its value
if 'variable' is unset - the result will be 'word'
$(var:=word} - if variable is set results in its value substituted
if variable is unset, it will be assigned to 'word'
such assignment will not work for positinal params(see 'shift')
and other special variables
${var:?word} - if variable is unset error with reason 'word' will be
generated, exit code of such construct will be 1
${var:+word} - if 'variable' is set, the result will be 'word',
(but variable's value will not be changed)
otherwise result will be EMPTY string
Example:
$ echo ${variable:-ls} - variable unset - ls used
> ls
$ export variable=1
$ echo ${variable:-ls} - variable is set- its value used
> 1
$ echo ${variable:+ls} - variable is set - ls used
> ls
$ echo ${variable1:+ls} - variable unset - empty line used
>
${!prefix} or ${!prefix@} - returns NAMES of existing variables
that starts from 'prefix.
Example:
$ echo ${!BASH}
> BASH BASHOPTS BASHPID BASH_ALIASES BASH_ARGC BASH_ARGV BASH_CMDS
string variables substitution:
${#var} - returns length of string in variable's value
Example:
$ var=123456789 #this could be interpreted as a string too now
> 9 #string length is 9
${#} or $# or ${#@} or ${#} - returns number of positional parameters
of the script being executed
${var:number} - return string from number to the end, spaces trimmed
variable is unchanged.
Example:
$ var="This string is to long."
$ echo ${var:5} #returns string from 5th symbol
> string is to long.
Example: spaces are trimmed:
$ echo ${var:5} | wc -c #count chars
$ 19
$ echo ${var:4} | wc -c #return starts from space
$ 19 #space is trimmed so same number of chars
${var: -number} - return string from end to number, spaces trimmed
NOTE - space between ':' and '-' signs
Example:
$ echo ${var: -5}
> long.
${var:number:length} - return string from number till end of lenth
Example:
$ echo ${var:5:6}
> string
${var: -number: -length} - return string number between number(from the
end) and length (also from the end)
NOTE: number must be > than length
Example:
$ echo ${var: -18: -2} #var is This string is to long.
> string is to lon
${@} - return all values of positional params
leaving spaces inside strings (like "$@" ) - bcs it know how
many arguments script has
${} is the same form, it seems
${@:num} - displays values of positional params but from num
$(@:1) - works same as ${@}
${@: -2} works , but starts from the end
${@:num:length} - same as with strings but with positional params
${@: -num: -length} - same as with strings but with positional params
${param#pattern} - finds shortest match and deletes it (lazy match)
Example:
foo="file.txt.gz"
${foo#.}
>txt.gz
${param##pattern} - finds longest match and deletes it (greedy match)
Example
${foo##.}
>.gz
${param%pattern} - same as # but deletes from the end of the file
Example:
foo=file.txt.gz
${foo%.} - note . instead of . in # example
>file.txt
${param%%pattern} - same as ##
${foo%%.}
>file
Search and replace:
${param/pattern/string} - replaces first occurance of pattern with string
${param//pattern/string} - replaces all occurances of pattern with string
${param/#pattern/string} - replaces only if at the beginning of the line
${param/%pattern/string} - replacesonly if at the end of the line
-get a VM and install Ubuntu to mess around and get used to the environment. The VM will keep you from damaging anything and acts as a failsafe.
-I also suggest reading about how to use BASH. This will help you familiarize yourself with Linux. This book is amazing.
I am a beginner too and just finished this book TLCL.Another one i would recommend is shell scripting bible.For most part use google to learn about commands and man page is your friend. I am more of a book kind of guy so never used video resources. Most important you should know where to look for help when stuck.
I found the book The Linux Command Line to be very useful. Good luck on your CEH!
It will take too long to explain how Linux handles such a thing differently. Read this book.
Every one should read it. I'm not a sponsor, dude!
Already good responses in here. If you're interested in a good book to learn a bit more, the concise Linux Pocket Guide is very handy. A longer book is The Linux Command Line: A Complete Introduction.
Some info on distro differences:
A few book recommendations: (books are generally the way to go)
A few online resources:
Videos/courses:
Some great past reddit threads I've saved for reference:
Just get these 2 books(all you'll need, peep the reviews for proof) and thank me later
Linux Command Line
How Linux Works
Going through a linux book, like this one, will get you over your linux hump. But otherwise, just doing stuff in Linux will get you going, like:
Once you get going, you're limited by your own imagination!
First of all I should say that I'm no expert in these things, but I'm sure other people will be able to make other suggestions.
>I plan on installing Linux as my OS (technically my first time)
If you're more used to Windows then the UI will be fairly easy to get used to, but the biggest change will be the command line. This is a really powerful but complex tool and I think the best way to get used to it is really just to dive in and use it as often as possible. MagPi have a book for it (Conquer the Command Line) to get you started, but if you wanted something more comprehensive I've spent some time reading The Linux Command Line and found it really helpful.
For Python I think I started out with Code Academy, but mostly picked it up as I went along. I'm currently reading Python Crash Course and I think it is pretty decent, although most people seem to recommend Learn Python the Hard Way (note the tiny link near the bottom of the page to read the book for free).
At the end of the day the most important thing is to take baby steps and take them often: when you've kept at it regularly for a few weeks it becomes a lot more easy.
I recommend How Linux Works and The Linux Command Line. Those will take a total beginner and take you through the basics up to shell scripting.
The Linux Command Line is a work book where you type what it says and follow along. How Linux Works is more of an explanation with less hands-on. I went through both at the same time as the chapters align very well, particularly at the beginning.
Obviously, you will want to read the documentation on the distro you decide to install. For a book, I would recommend The Linux Command Line.
When I was beginning to learn Linux back in the day, I used The Linux Command Line and have only good things to say about it. It must be one of the simple best books to introduce yourself to the command line and to how to use a modern Unix like system.
I'm reading "The Linux Command Line" book by William E. Shotts, Jr. A good primer for when you want to get into Linux. It reads well and it doesn't dump a ton of information on you at once.
​
Huh. It's a "Best Seller" now, lol. https://amzn.to/2zgHrzV
I have 3 semesters left so my plan has been to seek an internship next summer closer to graduating. Do you think it's unwise to wait that long? My independent study could be better but I've become proficient with Linux using Arch as my daily driver and reading through The Linux Command Line. I'm also going through The Basics of Hacking and Pentesting which had me set up a "lab". Just finished the recon chapter. Also proficient in Python/Java/C++ ("proficient" might be a bold claim, rust considered).
I would suggest just going through the table of contents for each book and picking the book that seems to contain a good amount of stuff you don't know.
This:
http://www.amazon.com/The-Linux-Command-Line-Introduction/dp/1593273894/ref=sr_1_1?ie=UTF8&qid=1334588018&sr=8-1
and maybe this:
http://linuxcommand.org/
Teach a man how to fish..
http://www.amazon.com/The-Linux-Command-Line-Introduction/dp/1593273894
I bought and read this book as a before taking OSCP, and it's been one of the most useful books I've read.
For Linux: The Linux Command Line: A Complete Introduction
For Python: Automate the Boring Stuff with Python: Practical Programming for Total Beginners
For R: The Book of R: A First Course in Programming and Statistics
These are all from No Starch Press, and I really like how they all function as complete introductions to their subjects. I've tried a number of programming books, but these have remained my go-to books for recommendations due to how well they build up basic principals for each concept or language. That said, I feel as though The Book of R is the weakest of the three, and maybe look into other recommendations for R if you get more replies.
EDIT:
Just realized that you asked for courses, not sources, my bad. Either way, I do encourage you to consider the above as alternatives to learning these concepts from online courses, as I've found them to be just as good if not better than some online courses I've seen.
"IT skills" is pretty broad. What is your IT degree- MIS, Cyber Security, Information Sciences, etc? The answer will really depend on what your degree is in and what your interests are. For example, I could tell you to study programming, but if your degree and interests align more with Cyber Security policy implementation, that might not be the best recommendation for you.
As somebody who has been on a few hiring committees, I'd say to work on your soft skills. In many cases, these are more important than technical capabilities. Specific soft skills I look for in new hires: organization, attention to detail, solid time management, communication, and self-sufficiency yet a team player. For us, we will take the candidate who doesn't know everything but has a good attitude and willingness to learn over the person who thinks they know everything and has a horrible attitude.
General technical skills you should toy around with: know your way around Active Directory in Windows, learn how to view event logs on a system (for Windows, hit your Start key and type in Computer Management), NIST Risk Management Framework, learn the parts of a computer and how to set them up and tear them apart. Learning Linux is also good- what I did to understand Linux better was purchase a Raspberry Pi and set it up to run Raspbian OS and RetroPie (to turn the Pi into a retro gaming machine). I also purchased The Linux Command Line and practice the commands from the book in the Raspbian terminal.
Also, before graduation, try to get some kind of internship, even if your major doesn't require one for graduation. It's a great opportunity for you to build hands-on experience and work in an IT environment doing real work. Oftentimes, you will learn something new in your internship that is not taught in school, and the experience might broaden your interests a bit (not to mention you may get a job offer or at least great references because of your internship!). If you need assistance in trying to figure out how to land a good internship, just let me know.
A few of my favorite books I reference and recommend. Just a note, many of these are older and can be purchased used for much less. Also if you can afford it, get a Safari subscription. I use my work Safari subscription but this alone has saved me from my book buying habit. Now I only buy "must have" books. :)
Official Ubuntu Server book - I really like this book as the writing style helped me "get it" with Linux. Kyle Rankin has a very good method of showing you the technology and then a quick run down to get the server working, followed by some admin tips. It's a just scratching the surface type of book but it's enough to get you started. I rarely use Ubuntu now, but this book helped me understand DNS and other topics that were IMHO harder to grasp from other books.
As a bonus, this book also has an entire chapter dedicated to troubleshooting. While this sounds obvious, it's a great read as it talks about dividing the problem, how to approach the facts, etc. Stuff a seasoned admin would know but might be hard to explain to a new admin.
The Linux Command Line: A Complete Introduction - You can read this book for free on the site, but having a paper copy is nice. As mentioned, you should have a very solid understanding of the command line. In my experience, I have seen co-workers struggle with basic shell scripting and even understanding how to make a single line for loop. This book covers the basics, moving to shell scripting and I think it's a good solid reference guide as well.
DevOps Troubleshooting: Linux Server Best Practices - This book is referenced a few times here but I'll throw another comment for it. Another book from Kyle Rankin and has the same straight to the point writing style. It's very quick reference and simple enough that you could give this to a new sysadmin and he or she could get started with some of the basic tools. While the book covers a good selection of basic services and tools, it's easy to get deeper into a chapter and find it's only discussing a handful of troubleshooting steps. The idea with this book is it's a quick reference guide, and if you want to get deeper into troubleshooting or performance, take a look at other books on the market. Either way, this is a great book I keep on my desk or reference through Safari.
UNIX and Linux System Administration Handbook (4th Edition) - Another popular book based on the comments here. This is a pretty big book, thin pages, but it's like a small brick of UNIX/Linux knowledge. While it's starting to get dated, it does give a great reference to many topics in the system administration world. The chapters can dive deep into the subject and offer more than enough information to get started but also understand the technology. The e-mail chapter I thought was great as well as the DNS. I think of this book as a overall guide and if I want to know more, I would read a book just on the subject, that's if I need more information. One thing to point out is this book makes use of different OS's so it's filled with references to Solaris, different UNIX versions, etc. Not a problem but just keep in mind the author may be talking about something outside the scope of vanilla Linux.
Shell Scripting: Expert Recipes for Linux, Bash and more - I found this book to be a good extenstion of the Linux Command Line book, but there are many many other Bash/Shell scripting books out there. The author has many of the topics discussed on his site but the book is a good reference for scripting. I can't stress enough how important shell scripting is. While it's good to know a more formal language like Python/Perl/etc, you are almost certain bash will be on the machine you are working on.
Systems Performance: Enterprise and the Cloud - I can't comment on this book beyond the first chapter, I'm still reading it now but it's reading similar to Brendan Gregg's site, and that's a great thing. If you don't know who this guy is, he's one of the top performance guys in the Solaris and now Linux world. He has some great infographics on his site, which I use for reference.
Use method for Linux
Linux Performance
Example of Linux performance monitoring tools
Hope this helps!
Only about half of the programming industry has a degree directly related to IT or programming. Most have college degrees in something, but in the end the most valuable thing to someone hiring in IT is skills. Once you have the skills, you just need to get noticed.
I would recommend you learn Linux administration and web development. (Or you could learn Windows too - I don't know Windows well so I can't comment on it. Linux and Mac OS X are somewhat more popular in the programming world, but if you're looking to get into IT, not programming, then Windows administration might be more common.)
A good book to learn Linux is "The Linux Command Line".
https://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894/
For learning web development, you could read "
Learning PHP, MySQL & JavaScript: With jQuery, CSS & HTML5"
https://www.amazon.com/Learning-PHP-MySQL-JavaScript-jQuery/dp/1491978910/
Codecademy would also really help you in here:
https://www.codecademy.com/
If you have any questions, feel free to PM me and I'll do my best to respond.
The Linux Command Line Its available for free (pdf on that site or here directly).
Also see the amazon reviews of it.
Here is the mobile version of your link
I was always pretty competent when it comes to windows, however I was a complete newb with Linux. So I read this book, The Linux Command Line and it answered the basics for me. It gave me enough knowledge to navigate with SSH and set up my SFTP server. Also helped understand what i was doing, instead of just reading mini tutorials here and there...Try it out.
Also, install homebrew for package management. Mac uses its own version of bash with some stuff slightly different than most linux distros, but they are pretty much the same.
OP Linux Command Line book, is an excellent place to start.
Any opinions on this book. I actually have it but have not had time for it
I would try CLI the hard way first. Pretty good intro to command line. Then I would read The Linux Command Line or study for Linux+.
If you want to get into sys admin, or a linux job never hurts to go Linux all the way. I would say Linux+, Network+, RHCSA, and CCNA can help you go a long way. If you like Linux getting RHCE will open more doors. You don't necessarily need to get all of these certs but it helps your knowledge and what people will quiz you on the phone. At one point I was doing about 2-3 phone interviews a week that would just ask about 20-30 random Network, Linux, Windows, and basic trouble shooting questions.
First thing first, there is nothing you can do with Linux that you couldn't do with Windows or a Mac. And similarly they can be made to do everything that Linux can. It's just a matter of how you go about getting those things done.
Learning sysadmin stuff will help with dev work (in my opinion as a former Linux sysadmin and current Java/Linux dev), but I'd bet you probably won't end up caring about setting up sendmail, bind, nfs, etc. which is a good chunk of the content of that book. I'd leaf through it and see if any of it seems interesting, but it'd probably make sense to return it.
If you're just looking to try to understand what linux is all about, it's tough to go wrong with http://linuxcommand.org/tlcl.php
It's free, but if you prefer dead tree versions like I do, you can buy it in a variety of places. Here it is on Amazon: https://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894
A lot of the command line stuff builds on itself, so don't feel bad if it doesn't make sense at first. Once you get comfortable with the shell, you can start dabbling in whatever else tickles your fancy.
I uses https://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894 when i first started learning Linux
Fair point, but it's not the window manager that keeps me away from arch, I just don't want to have to constantly be using the command line with a touchscreen keyboard, and my experience with Arch is that it's very command-line dependent and I'm just going to keep installing stuff that'll bring it closer to mint than it would be arch.
Plus, in between my calc, physics, and engineering classes, I don't really have the time to be learning a brand new operating system. But I did buy this book and when I have a little time I'll sit down for a few days and give Arch a good try.
ss64
NixCraft
[LinuxCommand.org]
(http://linuxcommand.org/)
[The Linux Command Line: A Complete Introduction]
(http://www.amazon.com/The-Linux-Command-Line-Introduction/dp/1593273894/)
Also William E. Shotts Jr.'s book is good too.
Hey, Scripting Guy! A Powershell genius, Ed Wilson. I will always be greatful of his wonderful Powershell examples.
edit: fixed links.
Load it onto an old computer and play with it.
Checkout this book: How Linux Works: What Every Superuser Should Know https://www.amazon.com/dp/1593275676/ref=cm_sw_r_cp_apa_fQ1MybTDN9VRP
Checkout this book: The Linux Command Line: A Complete Introduction https://www.amazon.com/dp/1593273894/ref=cm_sw_r_cp_apa_pR1MybNQRR2FK
Read Books: I recommend this, this and this.
> I really would love to hear if anyone has any thoughts on whether spending the time learning VIM is a good idea in this context.
When you ssh into a server and try to edit a small script, what will you do? Install a desktop environment to open up beloved VsCode or fire up trusty old Vim which is installed by default? Knowing basic Vim commands for text editing is a must have for any serious developer (you don't have to be expert, you just have to know enough to be comfortable with using it for small editing, for anything else use your main editor - as mentioned in the comments VsCode + Vim plugin is pretty awesome).
For learning bash I would recommend you The Linux Command Line
I would recommend getting a few "Linux" for dummies books. They provide a really good base of knowledge.
This is one I've read before, highly recommend: https://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894
When I first worked my first full time job, I couldn't understand for the life of me why anyone would use Terminal when SourceTree can get it all done, visually, with a modern GUI that's easy to understand.
Unfortunately, there was a time where SourceTree wasn't accessing my SSH tokens or something properly and I couldn't push. My senior told me, "Just use terminal" and I froze.
Terminal was terrifying. He drove and 3 minutes later we were back in business. He gave me this book:
The Linux Command Line: A Complete Introduction and told me to finish a chapter at least every week.
Later I learned about BashIt and themes and now I live in Terminal. You can do anything from Terminal. You can open up a Python interpreter, throw in some list values and decide where you're going to eat lunch and who's going to drive using a shuffle and random. You can scrape your entire developer directory for files that have the word Debug in them, even limited to file extensions like
.swiftor.py, using GREP.You can quickly edit a file on command using Vim, you can cat your README.md without having to switch tabs to your Github tab on your browser or even inside of the Finder folder.
There's so much you can do with Terminal.
This book is freakin awesome, i've used it and it's an amazing start and teaches you all sorts of stuff. I don't know how much information you actually know about the command line but this has helped me a lot. This book I have heard was pretty good but I unfortunatly haven't made my way to reading it. besides those two and actually installing and forcing yourself to use it everday there isn't much else you can do.
http://www.amazon.com/The-Linux-Command-Line-Introduction/dp/1593273894/ref=pd_sim_b_1
This is an excellent read if you are brand new to the command line.
Here's one of the best books that I've used. Immersing yourself in it and using it daily will go a very long way though.
http://www.amazon.com/The-Linux-Command-Line-Introduction/dp/1593273894
https://www.amazon.com.br/Linux-Command-Line-Complete-Introduction/dp/1593273894
A lot of CCNA folks I know are having a tougher time on the job market. The general direction of IT infrastructure is towards the Linux end of things, especially with cloud data. I used this book to understand Linux.
https://www.amazon.com/Linux-Command-Line-Complete-Introduction/dp/1593273894
This is a wonderful beginner's linux book. I loved it.
http://www.amazon.com/The-Linux-Command-Line-Introduction/dp/1593273894