Every user may have several independent passwords:

The andrew password is automatically generated when you get the andrew account, and it should be changed ASAP. It provides access to all the andrew computers and services, including the andrew e-mail account used for university official communication.

The math cluster password grants access to the Math Dept maintained computers and services including the qwe computers in room 6120, the parallel cluster, and to the @math.cmu.edu e-mail accounts. This password is generated when you request for a math computer account.

Some of the desktops in the Math Dept offices may have stand alone accounts. These accounts can be created upon request, and grant access to a specific desktop.

All the passwords can be changed with the "passwd" command.

Changing the password on one andrew computer will propagate the change on all the other andrew computers. Changing the password on one cluster computer will make the change on all the other cluster computers and on some of the desktops in the offices.

Since one week password puts at risk the data for all the users on that computer, please use hard to guess passwords.

Examples of bad passwords:

• based on a (slightly modified) dictionary word, even in a foreign language;
• based on some information connected to your person (car numbers, phone numbers, SSN, birth date, etc).

How to pick and remember an unbreakable password

Create a password from the first letters of the words in a sentence you can easily remember. E.g. the sentence: "Oh, how nice are Jane's shoes!" may generate the password "OhnaJ'ss" which won't be broken by existing brute force scans.