Changing an AIX password via script?

Question

I am trying to change a password of a user via script. I cannot use sudo as there is a feature that requires the user to change the password again if another user changes their password.

AIX is running on the system.

unfortunately, chpasswd is unavailable.

I have expected installed, but I am having trouble with that also.

here is what I thought would work

echo "oldpassword\nnewpasswd123\nnewpasswd123" | passwd user

However once run the script I am prompted with please enter user's old password shouldn't they all be echoed in?

I am a beginner with shell scripting and this has been baffled.

Solution 1

You can try:

echo "USERNAME:NEWPASSWORD" | chpasswd

Solution 2

Use GNU passwd stdin flag.

From the man page:

   --stdin
          This option is used to indicate that passwd should read the new password from standard input, which can be a pipe.

NOTE: Only for root user.

Example

$ adduser foo 
$ echo "NewPass" |passwd foo --stdin
Changing password for user foo.
passwd: all authentication tokens updated successfully.

Alternatively you can use expect, this simple code will do the trick:

#!/usr/bin/expect
spawn passwd foo
expect "password:"
send "Xcv15kl\r"
expect "Retype new password:"
send "Xcv15kl\r"
interact

Results

$ ./passwd.xp 
spawn passwd foo
Changing password for user foo.
New password: 
Retype new password: 
passwd: all authentication tokens updated successfully.

Solution 3

In addition to the other suggestions, you can also achieve this using a HEREDOC.

In your immediate case, this might look like:

$ /usr/bin/passwd root <<EOF
test
test
EOF

Solution 4

You need echo -e for the newline characters to take affect

you wrote

echo "oldpassword\nnewpasswd123\nnewpasswd123" | passwd user

you should try

echo -e "oldpassword\nnewpasswd123\nnewpasswd123" | passwd user

more than likely, you will not need the oldpassword\n portion of that command, you should just need the two new passwords. Don't forget to use single quotes around exclamation points!

echo -e "new"'!'"passwd123\nnew"'!'"passwd123" | passwd user

Solution 5

You can try :

echo -e "newpasswd123\nnnewpasswd123" | passwd user

View more solutions

Comments

[TehesFR]

I have the following code in a bash script and it works fine : useradd -s /bin/bash -g www-data -d /var/www/$vhost $Name; echo -e "$sshPasswd\n$sshPasswd" | passwd $Name; id $Name

[Grushton94]

yeah i tried that too: "echo oldpassword\nnewpasswd123\nnewpasswd123" | passwd --stdin user i get passwd: illegal option -- -

[Grushton94]

I su'd to root an i got the same "illegal option -- -"

[Grushton94]

seems like it, a lot of people's suggestions look like they should work, but don't.

[Grushton94]

thanks, but it's just this line echo -e "$password1\n$password1" | passwd $username that my system doesn't like

[Ikruzzz]

Did you provided the new password here? echo -e "$password1\n$password1" | passwd $username

[Mattisdada]

For it to work for me I had to change it to: echo "USERNAME:NEWPASSWORD" | sudo chpasswd when executing through a non sudo parent script

[Andrew Wolfe]

chpasswd to me seems like the right answer. Worked for me setting up a Docker image. I like the following (in bash) to avoid the 'echo' noise: chpasswd <<<"$USERNAME:$PASSWORD"

[Dr. Gianluigi Zane Zanettini]

Doesn't work on Ubuntu 16.04: passwd: unrecognized option '--stdin'

[Vercingatorix]

Newer versions do not support --stdin (e.g. openSUSE Leap 42.1; it worked in 12.1 but doesn't work anymore).

[pythonmts]

This script can be run in a linux machine. You can modify certain things according to your environment like mail relay server or change the limit in the password characters etc.

[12431234123412341234123]

this expect example do not work with the most locales. Maybe set it to C?

[Eduardo Baitello]

What if the password contains a "\n"? Such as my@secret\npasword123 ?

[Binita Bharati]

Great answer! Worked fine for me on Ubuntu. I had a similar requiremnt, but for first time setting (and not changing) a user's password. The mention of \n character along with -e option to seperate out the reply to the 2 password prompts really helped me.

[CoreyJJohnson]

This is still a simple answer if you can get over the word sudo and add the old password on a line.

[Taz]

echo username:password | chpasswd -c throws error