Difference between revisions of "BOSS-Linux/C2/Basics-of-System-Administration/English-timed"
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Latest revision as of 12:30, 24 March 2017
| 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 following- |
| 00:13 | adduser su |
| 00:16 | usermod userdel |
| 00:18 | id 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 | Let's 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 separate 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.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 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 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 let's 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 “-u" (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 'id's 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 'id's. |
| 08:08 | Let us now learn the commands for Group IDs. |
| 08:12 | Let's 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 | Let's 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 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 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 | Go to 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 *. (asterisk 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, please type: |
| 11:35 | du space -(hyphen)ch space *.(asterisk dot) txt and see what happens. |
| 11:46 | Let me go back to the slides. |
| 11:48 | To summarize, 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, |
| 12:24 | summarizes the Spoken Tutorial project. |
| 12:27 | If you do not have good bandwidth, you can download and watch it. |
| 12:31 | We conduct workshops using spoken tutorials. We also give certificates to those who pass an online test. Please contact us for more details. |
| 12:41 | Spoken Tutorial is a part of the “Talk to a Teacher” project, supported by the National Mission on Education through ICT (NMEICT), MHRD, Government of India. |
| 12:50 | More information is available on this url. |
| 12:55 | The script for this tutorial has been contributed by Praveen and this is Namita from IIT Bombay, signing off. Thank you for joining. |
