How to change your LST password
Connect to login server
In order to change your password, you have to connect to the server login.lst.uni-saarland.de via ssh. To do so just open a console (command promt, terminal, etc.) and type the following command:
ssh <your_username>@login.lst.uni-saarland.de
How to choose a good password
After logging in, you can create a new password with the command apg - Pick one!
apg -a0 -MNLC -t -m10 -x10
Passwords generated this way will take on average approximately 64 years to be broken by a 8xTitan-X GPU cluster node.
Change your password
Finally, use the passwd command to change the password to either a generated password or one you choose.
passwd
In case of a "kerberos" messages, please log out and log in and try again.
More information on passwords
A password should be
- kept secret
- changed on a regular basis
- not be easy to guess by others (like your Matrikelnummer or 'klausi1' for instance)
- new, do not reuse your old password(s)!
Diceware
A very good way to create hard to guess, yet easy to remember passwords (or passphrases) is to employ the "diceware" method using real world, physical dice. In short
- roll 5 dice 6 times,
- look up the word which corresponds to the result using an existing list of words,
- repeat until you have 6 words.
- Your 30 dice rolls yielded ~77 bits of entropy which is now encoded in the 6 words you chose.
A more detailled description including word lists for many languages can be found here:
http://world.std.com/~reinhold/diceware.html
Mini FAQ
Q: If I use more than 10 characters I am more secure, right?
A: No, not really. Currently we consider a 10 random character password "safe", but feel free to use longer passwords. Please consider that there are other ways to attack your account besides a brute force password attack. Be aware of the fact that there is no perfect security.
https://xkcd.com/538
Q: How about passwords I use on the Internet with my web browser?
A: We recommend using a password manager/password generator, like "keepassx", to create and store long (>30 chars) random passwords. We also recommend using the built in web browser password storage, but it is mandatory to use a strong (see above) master password (Firefox: Preferences -> Security -> Change Master Password) when doing so!