How to change your UNIX/Linux password

Instruction

It takes only a few steps to change your password.

Step 1: Access to the command line ...

... from Linux

If you are working on any GSI Linux machine (hostname begins with lx...) with a graphical user interface you only have to open a command line window (terminal), e.g. konsole for KDE or xterm. The corresponding button in the KDE panel looks like a monitor, simply click on this icon.

... from Windows

If you are working with Windows you'll have to open a session to a Linux machine via ssh using a Secure Shell Client. The following screenshots show the usage of putty:

ssh connection with putty

To start a connection you'll have to enter lx-pool.gsi.de as the "Host Name", then click on the button Open. In the console window you can enter your Linux account name and your actual (i.e. old) UNIX/Linux password (see screenshot for Step 2 below).

Step 1.5: Accepting the server key

If you are connecting to a ssh server for the first time you'll have to accept its ssh key. To ensure that the target belongs to the host group lx-pool.gsi.de you may compare its fingerprint with the value on this page, then click Ja, OK or any corresponding button of your Windows client. For Linux clients you'll have to type yes and hit [Return].

accepting the ssh server key

Step 2: Change your password on a Linux-machine

Use the command passwd There are password conditions on these machines:
  1. At least 8 characters
  2. English uppercase characters (A through Z)
  3. English lowercase characters (a through z)
  4. Base 10 digits (0 through 9)
  5. Nonalphanumeric characters (e.g., !, $, #, %)

Step 3: Close the session

Don't forget to close the command line session after finishing your work. You can logout by typing exit and pressing [Return]. In case of remote sessions the network connection is terminated also.

FAQ

Q: I've forgotten my old UNIX/Linux password, how can I reset it?
A: Please contact the UserHelpDesk (SB3 1.247, -2515).

Q: My proposed new password isn't accepted, why that?
A: You have to fulfil the password-rules stated in Step 2.

Q: How can I create a "strong" password?
A: Have a look at this website.
Topic revision: r16 - 2018-06-04, MatthiasPausch