PoojaMoolya: Created page with "{| border=1 |- || '''Time''' || '''Narration''' |- || 00:01 || Hello and welcome to the spoken tutorial on '''User''' '''Password Management '''in''' Linux.''' |- ||00:08 ||..."

2022-09-07T07:27:34Z

Created page with "{| border=1 |- || '''Time''' || '''Narration''' |- || 00:01 || Hello and welcome to the spoken tutorial on '''User''' '''Password Management '''in''' Linux.''' |- ||00:08 ||..."

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|| '''Time'''
|| '''Narration'''

|-
|| 00:01
|| Hello and welcome to the spoken tutorial on '''User''' '''Password Management '''in''' Linux.'''

|-
||00:08
|| In this tutorial we will learn about

Changing''' user password'''

|-
|| 00:14
|| Locking and unlocking a '''password'''

|-
|| 00:17
||'''Password '''removal

|-
|| 00:20
|| Changing the '''password '''expiry information

|-
|| 00:24
|| We will do this through some examples.

|-
|| 00:28
|| To record this tutorial, I am using '''Ubuntu Linux 16.04 OS'''

|-
|| 00:35
|| To practice this tutorial, you should have gone through earlier '''Linux System Administration '''tutorials''' '''on this website and

|-
|| 00:46
|| You must have '''root access''' to your computer.

|-
|| 00:51
|| In this tutorial we will learn about '''passwd command'''.

|-
|| 00:56
|| As the name suggests, '''passwd command''' is used to change the '''password''' of '''users'''.

|-
|| 01:04
|| Earlier in the series, we had created a '''user amit.'''

|-
|| 01:09
|| Now suppose he forgot his '''password.'''

|-
|| 01:13
|| So as a '''system administrator''', you have to reset his '''password'''.

|-
|| 01:19
|| Let’s learn how to do this.
|-
|| 01:22
|| Open the '''Terminal '''by pressing '''Ctrl, Alt and T '''keys simultaneously on the keyboard.
|-
|| 01:31
|| First, we should login as the '''superuser '''or '''root user'''.

|-
|| 01:37
|| To do so type: '''sudo space su '''

And press '''Enter.'''
|-
|| 01:45
|| Type our '''password '''and then press '''Enter'''.
|-
|| 01:50
|| Notice, our '''login prompt '''has changed to''' '''a '''hash''' symbol.

|-
|| 01:55
|| This indicates that we are in the '''root user '''mode.
|-
|| 02:00
|| Here onwards, please remember to press the '''Enter''' key after typing each '''command'''.
|-
|| 02:07
|| On the '''terminal '''type '''passwd space amit '''
|-
|| 02:13
|| It will ask you to type a new '''password'''.

|-
|| 02:17
|| Type the new '''password''', say '''new_pass''' and press '''Enter.'''

|-
|| 02:24
|| Retype the same '''password''' and press '''Enter '''again.
|-
|| 02:29
|| The '''password '''has now changed.
|-
|| 02:32
|| As a '''system admin''', you may need to change the '''password''' for the '''root account''' itself.

|-
|| 02:38
|| To do so, you should type '''passwd '''and press '''Enter.'''

|-
|| 02:43
|| When prompted, you should type your new '''password''' and press '''Enter.'''
|-
|| 02:49
|| It will prompt you to type the '''password''' once again.

|-
|| 02:53
|| So retype the same '''password '''and press '''Enter'''.

|-
|| 02:58
|| You will get a message that the '''password '''has been updated successfully.
|-
|| 03:04
|| '''Password status '''information related to a '''user account''' can be displayed, as well.

|-
|| 03:11
|| This is done by using''' hyphen capital S''' with the '''passwd command.'''
|-
|| 03:18
|| Switch to the '''terminal.'''
|-
|| 03:21
|| Type '''passwd space hyphen '''capital '''S space amit'''
|-
|| 03:28
|| The output shows seven space separated '''fields'''.

Let us understand them one by one.
|-
|| 03:36
|| Suppose, your output shows this.

|-
|| 03:40
|| The first '''field''' is the '''username'''.

|-
|| 03:44
|| The second '''field''' indicates whether the '''user account''':

has a '''locked password (L), ''' has no '''password (NP), ''' or has a usable '''password (P)'''.

|-
|| 03:58
|| The third '''field '''gives the date of the last''' password change'''.

|-
|| 04:04
|| Fourth to seventh '''fields''' indicate '''password''' expiry information.
|-
|| 04:10
|| The '''fields''' are '''minimum age, maximum age, warning period, '''and''' inactivity period''' for the '''password'''.

|-
|| 04:22
|| These '''ages''' are expressed in days.

|-
|| 04:26
|| We will discuss these in a couple of minutes.
|-
|| 04:30
|| Notice '''user amit''' now has a '''usable password'''.

|-
|| 04:35
|| We have changed our '''password''' just now.

|-
|| 04:39
|| So, the third '''field''' is showing today’s date 16th Jan 2019.

It may be different in your case.
|-
|| 04:50
|| As a '''system admin''', you may need to check the '''password status '''of all the '''user accounts'''.

|-
|| 04:57
|| For this, we will use the option '''small a''' along with '''capital S'''.

|-
|| 05:04
|| Type '''passwd space hyphen small a capital S'''
|-
|| 05:12
|| Notice, the '''password status '''of the '''user accounts '''are shown here.
|-
|| 05:18
|| Now, as a '''system admin '''you may need to lock a '''user’s password '''for some reason.

|-
|| 05:25
|| To lock the '''password''' for '''user amit,''' type '''passwd space hyphen l space amit'''
|-
|| 05:36
|| Press the '''up arrow key''' thrice to get back the command for showing '''password status '''of user''' amit.'''

|-
|| 05:44
|| Notice, the '''status '''is now '''L'''.

|-
|| 05:48
|| This means the '''password '''is locked now.
|-
|| 05:52
|| We also know about '''/etc/shadow file'''.

|-
|| 05:58
|| It stores the '''encrypted''' values of all '''users’ passwords.'''

|-
|| 06:03
|| Type '''cat space /etc/shadow'''

|-
|| 06:12
|| Notice, you have an '''exclamation mark''' added before the '''encrypted password''' for the '''user amit.'''

|-
|| 06:20
|| Now, this '''password field''' cannot be matched by any possible '''encrypted''' value.
|-
|| 06:27
|| Note that, this will not disable the '''user account.''' It will simply lock the '''password'''.
|-
|| 06:34
|| So now the '''user''' cannot use this '''password''' to '''login''' to the '''system.'''

|-
|| 06:40
|| The '''user '''cannot change the '''password'''.

|-
||06:44
|| But, the '''user '''can''' '''still '''login '''to the '''user account '''by any other mechanism.

|-
|| 06:51
|| It is possible to do so by other ways, which do not refer to the '''passwd file'''.

|-
|| 06:58
|| For example: '''ssh key authentication'''.

|-
|| 07:03
|| '''Login '''through '''ssh key authentication''' will be covered in subsequent tutorials.
|-
|| 07:09
|| Now, to unlock the '''password''', type: '''passwd space hyphen u space amit'''

|-
|| 07:19
|| This will restore the '''password''' to its original value.
|-
|| 07:24
|| Recall the '''command '''for showing the '''password status '''for the user '''amit'''

|-
||07:30
|| Notice, the '''Status '''is now '''P'''.

|-
|| 07:34
|| Which means that the '''password '''is usable now.
|-
|| 07:38
|| Recall the '''command '''to display '''/etc/shadow file.'''

|-
|| 07:45
|| Notice that the''' exclamation mark''' is removed now for the '''user amit'''.

|-
|| 07:51
|| It means the '''password '''is not locked anymore.
|-
|| 07:56
|| As system admin, you can delete a '''user’s password '''also.

|-
|| 08:02
|| To delete the '''password '''for '''user amit''', type

'''passwd space -d space amit'''
|-
|| 08:12
|| So, the '''password '''for the '''user amit '''has been removed.

|-
|| 08:17
|| It is a quick way to disable a '''user’s password.'''
|-
|| 08:21
|| Recall the '''command '''for showing the '''password status '''for the user '''amit'''
|-
|| 08:27
|| Notice that the '''password status '''is now '''NP'''.

So, '''password '''is not set for '''user amit.'''
|-
|| 08:37
|| Next, let’s look at '''password '''expiry information.

|-
|| 08:42
|| To display the '''user’s password '''expiry information, we had used '''passwd hyphen capital S '''option

|-
|| 08:52
|| We can also use''' chage command '''with the option '''small L'''

|-
|| 08:59
|| This gives the output in a more user-friendly format.

|-
|| 09:04
|| To view the information about''' user amit, '''switch to the '''terminal''' and type:

'''chage space hyphen l space amit'''
|-
|| 09:17
|| Notice that we have a lot of information in the output.

|-
|| 09:22
|| Let us look at them one by one.
|-
|| 09:25
|| See, it is showing the minimum number of days between '''password change''' as 0

|-
|| 09:32
|| A value of 0 indicates that the '''user''' is allowed to change his or her '''password '''anytime.

|-
|| 09:40
|| The system admin can set minimum number of days between '''password changes '''using '''passwd '''with '''-n''' option.
|-
|| 09:50
|| Let us set this, so that the '''user amit '''can change his '''password '''only after 30 days from the previous one.

|-
|| 09:59
|| To do that, type '''passwd space -n space 30 space amit'''

|-
|| 10:09
|| Recall the '''chage command '''for the user '''amit'''.

|-
|| 10:13
|| So now, '''amit''' is allowed to change his '''password''' only after 30 days.

|-
|| 10:20
|| Notice, maximum number of days between '''password change''' is shown as 99999 days.

It is a very long time.

|-
|| 10:32
|| It practically means that the '''password''' will never expire.
|-
|| 10:37
|| To customize the maximum number of days for which the '''user password''' remains valid, use '''-x option'''

|-
|| 10:45
|| So let us change the setting such that '''user amit'''’s '''password '''is set to a maximum of 180 days.

|-
|| 10:55
|| Type: '''passwd space hyphen x space 180 space amit'''
|-
|| 11:04
|| Recall the '''chage command '''for the user '''amit'''.
|-
|| 11:08
|| This message indicates that '''amit’s password '''will be valid for 180 days only.

|-
|| 11:15
|| After 180 days, '''user amit '''will have to change his '''password'''.
|-
|| 11:21
|| Notice, for now, the '''user '''will get a warning message 7 days before the '''password '''expires.

|-
|| 11:29
|| You can also set specific number of days for the warning message before the '''password''' expires.

Let me set it as 10 days.
|-
|| 11:40
|| Type '''passwd space hyphen w space 10 space amit '''

|-
|| 11:49
|| Let’s recall the '''chage command '''for the user '''amit'''.

|-
|| 11:54
|| So, this will give warning message to the '''user '''10 days before '''password '''expiry.

|-
|| 12:01
|| The message will state that his or her '''password '''is going to expire.
|-
|| 12:07
|| How can we force the '''user''' to change their '''password '''during their next '''login'''?

|-
|| 12:13
|| For that we have to use '''passwd command '''with '''-e option.'''

|-
|| 12:20
|| Type '''passwd space -e space amit'''

|-
|| 12:26
|| It will expire the '''user’s password '''immediately.

|-
|| 12:31
|| So, the '''user '''will be forced to change their '''password '''at their next '''login '''attempt.
|-
|| 12:38
|| Notice, it says '''password '''expiry information has changed.
|-
|| 12:44
|| Recall the '''chage command '''for the user '''amit'''.
|-
|| 12:49
|| So, '''password''' must be changed.
|-
|| 12:53
|| Now suppose the '''user’s password '''has already expired.

|-
|| 12:58
|| After '''password '''expiry, you can give the '''user '''a''' grace period'''.

|-
|| 13:04
|| The '''user '''will be able to change the '''login password '''within that '''grace period'''.

|-
|| 13:10
|| Otherwise, the '''user account '''will be disabled permanently.

|-
|| 13:15
|| That '''grace period '''is called '''period of inactivity'''.

|-
|| 13:20
|| You can set this '''inactivity period '''with the help of '''hyphen i option'''.

|-
|| 13:26
|| Let us set the '''grace period '''as 20 days for '''user amit.'''

|-
|| 13:32
|| Type '''passwd space hyphen i space 20 space amit'''
|-
|| 13:40
|| Notice, the '''user password '''information has now changed.
|-
|| 13:45
|| Till now, we have executed '''passwd command '''with only one option at a time.

|-
|| 13:52
|| Please note, you can also combine multiple '''options '''in a single '''command'''.
|-
|| 13:58
|| For example:

This '''command '''sets the minimum and maximum days between '''password change '''as 10 and 20 respectively.
|-
|| 14:10
|| To exit from the '''root user access''',

Type '''exit'''
|-
|| 14:15
|| This brings us to the end of this tutorial.

Let us summarize.
|-
|| 14:22
|| In this tutorial we learnt about-

Changing''' password'''

|-
|| 14:27
|| Locking and unlocking '''password'''

|-
|| 14:30
|| '''Password '''removal

|-
|| 14:32
|| Changing''' password '''expiry information

|-
|| 14:36
|| As an assignment-

Change '''password''' expiry information of the '''user amit '''as follows

|-
|| 14:44
|| Minimum number of days between '''password''' change: 20 days

|-
|| 14:49
|| Maximum number of days between '''password''' change: 100 days

|-
|| 14:54
|| '''Period of inactivity''': 5 days

|-
|| 14:58
|| Use a single '''command''' to execute all of the above

|-
|| 15:03
|| Check the '''password '''expiry information by using '''chage command'''

|-
|| 15:09
|| Check '''password status '''by using the '''passwd command '''with the required '''option'''

|-
|| 15:16
|| The video at the following link summarises the Spoken Tutorial project.

Please download and watch it.
|-
||15:25
|| The '''Spoken Tutorial Project''' team conducts workshops and gives certificates.

For more details, please write to us.
|-
|| 15:35
|| Please post your timed queries in this forum.
|-
|| 15:39
|| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

|-
|| 15:45
|| The script has been contributed by Antara and this is Praveen from IIT Bombay signing off.

Thank you for joining.
|-
|}

Linux-for-Sys-Ads/C2/User-Password-Management/English-timed - Revision history

PoojaMoolya: Created page with "{| border=1 |- || '''Time''' || '''Narration''' |- || 00:01 || Hello and welcome to the spoken tutorial on '''User''' '''Password Management '''in''' Linux.''' |- ||00:08 ||..."