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[Intro Music]

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We have just explored how to create

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new users using such command as

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'useradd', and using corresponding

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'userdel' command, we have deleted

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users. Now let me explain you how

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you could create a new user using

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command 'adduser'. And also

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afterwards, I'll tell you how to

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create new groups and assign users

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to some custom groups. Because by

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default, Linux creates a group with

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the same name as username you

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create. Alright, let's now enter,

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'adduser' command; and next,

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let's type username of the user I

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want to create. And here you'll see

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some prompts. First of all, you'll

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see that new user was added. After

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that new group, 'bogdan' was created.

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And here in parenthesis, you'll see

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actually ID for specific user,

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because every user has specific

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ID. Next, you see that new user

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'bogdan' was assigned to 'bogdan'

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group. Afterwards new home directory

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was created automatically, and path

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to this directory is here,

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'/home/bogdan'. And next, after

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this step, you new files were

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copied into the home directory for

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this user. And basically here after

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this command, you will see the same

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three files that we have seen in

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the previous lecture after 'useradd'

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command. And here, we are

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immediately prompted to create a

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new password for this user. And you

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see that this command 'adduser' is

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actually interactive conversation

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for creation of the new user. All

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right, let's enter here new

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password. Again, let me choose some

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something really strong, '123'; retype '123'.

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And you'll see that password was

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updated successfully. Afterwards,

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you could set such parameters as

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'Full Name', 'Room Number', 'Work Phone',

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'Home Phone', 'Other'; and if this

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information is correct, just simply

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type Yes, and press Enter; or just

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press Enter. And now we're all set,

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new user 'bogdan' was successfully

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created. Let's verify that. Let's

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clear terminal. And first let's

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have a look at contents of the home

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directory. And here I see new

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folder 'bogdan'. And it's a good

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sign, it seems that this new home

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directory was created

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automatically. Let's have a look at

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contents of this directory; and

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let's add here options '-la'; and

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I'll see three hidden files, '.bash_logout',

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'.bashrc', and '.profile'; and

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notice username and group for

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those three files. You see that

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owner and group for all files is

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set to new user, 'bogdan'; and

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that means that this user has full

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access to those files. Actually,

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here you see permissions for every

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file; and this user 'bogdan' is

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able to read, write, but not execute;

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other group users are able only to

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read those files; and remaining users

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are also able only to read those

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files. And that means that any

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other users will not be able to modify

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those files like '.bash_logout', '.bashrc',

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and profile. Alright, that's how

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this home directory looks like for

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this particular newly created user.

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Let me now clear terminal and enter

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following command, 'cat /etc/

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passwd', let's press Enter, and here

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in output of this command at the

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very end, I'll see information

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about newly created user. Here I

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see username, here is User ID, it is

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1000, next comes path to home

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directory for this particular user,

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and finally, you see default shell

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for this user. And here in this

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case, you see that this default

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shell was set to 'bash' shell. And

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that is the difference between 'adduser'

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and 'useradd' command. We have

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seen that in 'useradd' command

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default shell is set to 'sh', but when

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you create a new user using

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'adduser' command, then default shell

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will be set to 'bash', and the reason

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for that is that initial default

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configuration settings are located

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in other file if you use 'adduser'

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command. Let me show you location

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of this file. Let me clear terminal

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and type 'cat /etc/adduser' first

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step, and you'll see that file name

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will be autocompleted to

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'adduser.conf'. Let's have a look at the

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contents of this configuration

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file. And here in this output let's

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find the setting for bash shell, it

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should be somewhere at the

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beginning. And yes, here is the

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setting 'DSHELL=/bin/

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bash'; and that means that default

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shell for all users that are

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created using 'adduser' command will be set to 'bash'.

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And actually, you're able to modify

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this configuration file, same as we

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did with configuration file for

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'useradd' command, if you want, of

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course. Alright, that's how this

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configuration file looks like. And

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that's how we have just created a

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new user using 'adduser' command.

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Great. Let's now try to login as

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'bogdan' user. Let's type 'su

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-', and next comes 'bogdan',

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please recap that '-' stands for

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'-' option or '-l' or '--

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login' option. And with this option,

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we will login into the home

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directory for a particular user.

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Let's press Enter, type 'pwd', and yes,

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now I'm inside of the home

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directory for 'bogdan' user. And

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here you see that the command prompt was

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changed. And here now I see new

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user 'bogdan'. If I enter 'whoami',

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I'll see same output here.

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Great. That is how we were able to

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login under custom user that we

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have just created. And of course,

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now I'm able to create some files

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in this home directory. Let's

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create a new file, let's say '1.txt',

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and let's list contents

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of home directory. And I'll see

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newly created file. And you'll see

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that owner of this file is of course

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'bogdan'. And here you see

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'bogdan' because it is the name of the

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group that was automatically

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created for new user 'bogdan'.

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And here are permissions for this

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newly created file. Alright, that's

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how we are able to interact with

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system under custom user. And next

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let's talk a bit about permissions

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for files. And in the next lecture,

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I'll try to create a new file as

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root user, and afterwards try to

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modify this file under 'bogdan's'

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account. Let's try that in the next

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lecture. Bye-Bye.

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[no audio]