Users, Groups and Permissions in Linux

Note: We Demonstrate Linux using Ubuntu Server 10.04

Info

Level: Intermediate
Presenter: Eli the Computer Guy
Date Created: September, 16 2010
Length of Class: 37 Minutes
Tracks

Linux
Prerequisites

Introduction to Linux
Installing Linux
Basic Linux Tasks
VIM for File Editing
Navigation in Linux
Purpose of Class

This class teaches students how to manage users, groups and permissions in a Linux enviornment.
Topics Covered

Adding and Deleting Users
Editing the passwd File Which Contains User Configurations
Changing User Passwords
Adding and Deleting Groups
Adding and Deleting Users from Groups
Editing the group Configuration File
Understanding Permission Numbering System
Changing User and Group Ownership for Files and Folders
Class Notes

Users
Add User = sudo adduser username
Change User password = sudo passwd username
Delete User = sudo userdel username
Edit Users Configuration File = sudo vim /etc/passwd (shows usernames, names of users, home directories)
Groups
Sudo groupadd groupname
Sudo groupdel groupname
Sudo vim /etc/group (shows groups and users)
Permissions
Numbers = owner/group/everyone else
4 = read, 2 = write, 1 = execute
To Chanege Permissions of a File or Folder = sudo chmod 777 file/folder (-R for recursive)
Changing Ownership
To Change User Ownership = sudo chown -R username file/folder
To Change Group Ownership =sudo chgrp --R groupname file/folder
-R for Recursive for Folders

[ethanharte]

this video is probably the most useful video on the entire internet. Thanks

[raisedbyreels]

Best investment of 37 mins I could of made.. Thanks for taking the time !

[olaniyijosephadesunloye]

I salute you. Two things, its different when you know something and you are able to pass the same knowledge to others. your teaching is exceptional. My instructors in school makes it much more complicated and hard. But watching your video Eli has made life much easier for me . thank you once again.

[darrellmillner]

Extraordinary experience. Your straight-forward style made all the difference. Thank you

[dansfitnessvlog]

This guy is amazing. I learned a lot from Eli before I started my journey in the IT industry back in 2017. I have been jobless for about three years now, but I’m about to apply again for an IT staff position. Several companies require qualifications for a better understanding of Linux or more advanced knowledge. It took me about 4-5 hours to finish all of his 9 video tutorials to wakeup and refresh the learnings i had before. Even though the videos are old, they are still very effective. Thanks Eli! the best!

[sushiltiwari]

#respect to your teaching skills. Some teacher make subject complicated and hard to understand but some teachers make complicated subject soo easy to understand you are one of them

[itpugil]

he is like my main online linux instructor, learned almost everything i know about linux from him :)

[murraybrowning]

Thanks Eli, this stuff's amazing. Can't begin to express how thankful I am for making this both free and public.

[israraslam]

I found the explanation by Douglas Rumbough very simple. linux permissions are in sets of 3, USER|GROUP|EVERYONE so to give a test.txt permissions you just remember the following:

R =4
w=2
x =1
NONE = 0

you want USER(owner) to have all permissions 4+2+1 = 7
you want GROUP to have read+write 4+2 = 6
you want EVERYONE ele to have no permissions 0+0+0 = 0

so your permissions for the test.txt would be 760

[frakk]

Very useful, and understandable for a non English natives as well

Parts start from:

Prolog
User mgm exp. : adduser, deluser 1m31s -
dem. 05m50s -
Groups mgm exp. : addgroup, delgroup 10m46s -
dem. 16m40s -
Permissions exp. : chmod 20m40s
dem. 27m20s -
Ownership exp. : chown, chgrp 30m22s -
dem. 33m10s -

Final thoughts 35m23s -

exp:explanation, dem.:demonstration

[animatrix]

Why cant I find a teacher like you at my school? Your amazing, your knowledgeable, but also know how to translate the knowledge to those hoping to aspire to greater heights. I am very grateful I found your channel, simply amazing!

[rufaidaalzoubi]

Dear Eli, this is the best YouTube video. I refer to this video almost every month :) I cannot memorize the commands, that is why I use this as a reference ... Many thanks for posting this.

[jaiyesh]

Eli I have watched almost all your videos but this is the first one I am commenting on.

YOU ARE AMAZING. REALLY!!

Thank you so much for these very informational and easy to understand videos. All the people disliking your video are crazy.

Keep up the amazing work!!

[alexandraclaudiaman]

Linux isn't my domain of working. I want to learn it. So, I'm a beginner and you explain this it well! Congrats

[alleniamathews]

As always you take something that professors make sound complicated and show how simple it is. Great job I would be lost without these videos.

[aleksandarpetrovic]

Amazing video, after 7 years in Linux I finally understand user, group, and permissions :)))) Thanks a lot, man!

[fytubevw]

Still rocking, one of the clearest guides to user management and basics of Access control.

[Bbaass_TMH]

Eli, this video is very helpful. I have been promoted to backend administrator on a Minecraft multiplayer server about a year ago. That server runs Linux. Before I was promoted, I had never used Linux before. Since then, I have found this video, and have checked it several times again during the year.

Thank you for making this video!

[josephbatish]

eli I thank you and appreciate your work
You're an amazing teacher

[deleatur]

Thank you SO MUCH! I've been dealing with this issue for years (no exaggeration) because (now I see) I'd started with wrong asumptions. Superb explanation! Thx again!