BOSS-Linux/C2/Basics-of-System-Administration/English-timed

Time	Narration
00:02	Hello and welcome to the Spoken Tutorial on Basics of System Administration in Linux.
00:09	In this tutorial we will learn the followings.
00:13	adduser
00:14	su
00:16	usermod
00:17	userdel
00:18	id
00:19	du
00:20	df
00:22	I am using Linux for this tutorial.
00:27	As a prerequisite please go through the spoken tutorial on General Purpose Utilities in Linux which is available on this website
00:39	One must have admin access in order to execute the commands shown.
00:47	Let us first learn how to create a new user.
00:53	The adduser command will create a new user login for us along with authentication.
01:01	We can add any user account with the help of sudo command.
01:06	Let me give you a brief explanation about the sudo command.
01:11	Sudo command allows the administrative user to execute a command as a super user.
01:19	The sudo command has many options. We will learn about the options as we go further in this tutorial.
01:27	Lets now learn how to create a New User.
01:32	I have already invoked the Terminal here.
01:36	Here type the command sudo space adduser and press Enter.
01:45	You will be prompted for a password.
01:48	I will give the Admin password here and Enter.
01:54	The typed password on the terminal, is not visible.
01:58	So we have to type the password carefully.
02:03	Once done, a message adduser : Only one or two names allowed is displayed.
02:14	So let us create a new user account named duck.
02:21	Type the command :
02:23	sudo space adduser space duck, and press Enter.
02:33	We have created a new user called duck.
02:36	In the process of creating a new user, a seperate home directory for that user has also been created.
02:46	Please note that we will be prompted for a new password for the user duck.
02:52	Type the password of your choice, in my case i am going to type duck as the password and press Enter.
03:04	Please type the new password again.
03:07	The password is asked twice for security reasons and for confirmation.
03:13	Now our password for the new user is updated.
03:18	We will be asked for other details too.
03:22	But for the time being, I will enter only the Full Name as duck and leave the rest of the details blank by pressing the Enter key.
03:33	Enter.
03:34	I will confirm this by entering “y”.
03:39	This is to confirm that all the information is correct.
03:43	Let us now check, if the user account has been created.
03:48	To do this, please type the at the command prompt
03:51	ls /(slash) home
03:56	and press Enter.
03:58	To show the list of users in the home folder this command is used.
04:05	And here is our newly created user named duck.
04:10	Let me switch back to the slides.
04:13	Now the next command is the su command
04:18	su stands for Switch User.
04:21	This command is useful for switching from the current user to another user.
04:26	Let us go to the Terminal now.
04:30	Enter the command su space hyphen space duck on the terminal and press Enter.
04:41	You will be prompted for a password.
04:44	I shall type the user duck password here please recall that it was duck itself.
04:51	Please notice that, the Terminal switches from the previous user to the new user, which is “duck” in our case.
05:02	To logout from this user, type logout and hit Enter.
05:10	Now the terminal logs out from the current user duck and comes back to the previous user account, which is vinhai in our case.
05:18	Let us learn about the usermod command.
05:23	The usermod command
05:24	Enables a super user or root user to modify the settings of other user accounts such as
05:33	Change the password to no password or empty password.
05:37	Show the date on which the user account will be disabled.
05:42	Let us try this command and see.
05:44	Let me switch to the terminal now.
05:46	Let me show you how to set a date of expiry for the user account duck.
05:52	Here at the command prompt type
05:56	sudo space usermod space -(hyphen)e space 2012-(hyphen)12-(hyphen)27 space duck
06:21	and press Enter.
06:25	The user account expiry date is set as mentioned in the command here with the help of the option “-e”.
06:34	Now you have set an expiry date for the user account duck.
06:39	Let us now talk about the uid and gid commands.
06:45	id – command is used to check the identities of all the users and groups
06:51	To know about the identity of the user, we use id space -(hyphen)u.
07:00	To know about the identity of the group users, it is id space -(hyphen)g
07:08	Now lets work on this.
07:10	At the terminal, let us type id and press Enter.
07:17	Now we can see the User IDs and Group IDs on the system that we are using
07:25	To get only the user id, we use “-(hyphen)u” option.
07:30	Let us type the command, id space -(hyphen)u
07:36	and press enter.
07:38	Now we can see only the ids of the users.
07:42	But what if we need to know the names of the users?
07:47	To find that out, we will type
07:50	id space -(hyphen)n space -(hyphen)u on the terminal here and press Enter.
08:00	Now we can see the names of the users instead of their ids.
08:08	Let us now learn the commands for Group IDs.
08:12	Lets type id space -(hyphen)g.
08:17	Here we can see the group ids.
08:20	If we want to view all the current user's group IDs, type
08:26	id space -(hyphen) (capital)G and press Enter.
08:32	Please notice that I have typed G in capital letter.
08:38	See the result for yourself.
08:40	Now let us learn how to delete a user account.
08:44	For this we use userdel command.
08:48	We can delete an user account permanently with the help of the userdel command.
08:54	Lets try this on the terminal.
08:56	Here type sudo space userdel space -(hyphen)r space duck.
09:09	I have used the -(hyphen)r option.
09:12	This is to remove the user along with his home directory.
09:17	Let us press Enter and see what happens.
09:21	Now the user duck has been deleted.
09:25	Check this by typing
09:28	ls space /(slash)home and press the Enter.
09:35	We will find that, the user account duck has been deleted.
09:40	Let me go back to the slides now.
09:43	Some of the useful commands in Linux System Administration are “df” and “du”
09:50	The df command gives a report on the free space available on the disk.
09:55	And the du command gives a report on how much space a file has occupied.
10:00	Please try these two commands and find the output for yourself as an assignment.
10:06	Let us shift to the terminal, I shall show you a few useful options used with the “df” command.
10:13	Please type df space -(hyphen)h and press Enter.
10:20	Here it shows the size of the File system, and the space is used.
10:25	It also shows the space mounted on in a human readable format.
10:34	Let us now try some options with the “du” command
10:37	At this point i assume that you have created some text files in your home folder.
10:44	If not please refer to the tutorial on General Purpose Utilities in Linux
10:51	I have already created some text files in my home directory to execute the commands.
10:58	Goto home folder on the terminal by typing
11:03	cd space /(slash) home and press Enter.
11:07	Then type du space -(hyphen)s space *. (astrix) dot txt and press enter.
11:21	This command will give you a report on the txt files available in the directory along with its file sizes.
11:30	As an assignment, at the command prompt type
11:35	du space -(hyphen)ch space *.(astrix dot)txt and see what happens.
11:46	Let me go back to the slides.
11:48	To summarise, we have learnt:
11:51	adduser command to create a new user.
11:53	“su” command to switch from one user to another user.
11:56	“usermod” command to change the user account settings.
12:00	“userdel” command to delete the user account.
12:03	id command to know the information about user ids and group ids.
12:07	“df” command to check the file system size and its availability.
12:11	“du” command to check the space occupied by a file.
12:15	This brings us to the end of this tutorial on “Basics of system administration”
12.20	The video available at this url,
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12:55	This script for this tutorial has been contributed by Praveen and this is Namita from IIT Bombay signing off. Thank you for joining

Contributors and Content Editors

PoojaMoolya, Pratik kamble, Sandhya.np14