Logging In

Logging in is a simple process. Sit down at a node, and press Return if necessary to get the login prompt (the workstations blank their screens after a while to prevent burn-in). Type your NetID and password where indicated, choose a kernel if desired and press Go.

Changing Your Password

To change your password go to Yale ITS' password maintenance page.

For tips on password protection please see ITS' article Protecting your Yale NetID.

Keep in mind that anyone who knows your password has unrestricted access to your account and the information within. You should be the only person with this access. Anyone who logs into your account has the ability to alter or damage the data within, as well as to represent him or herself as you on the internet. To make sure that only you have access to your account, please observe these guidelines:

• Never give your password to anyone. Likewise, don't try to obtain other people's passwords. If you need to share files or programs with someone else, you can provide limited access to certain files and directories by making them world- or group-readable, or by using a collaborative development system like RCS or CVS.
• If you suspect that someone is tampering with your account, change your password. It is actually a good idea to change your password on a regular basis (once a month is reasonable, more frequently if you are paranoid).
• Do not write your password down or save it in a file on your account. Such information all too easily ends up in the wrong hands.

Changing Your Shell

When you log in and get to a prompt the operating system starts a program called a shell, which allows you to launch programs and interact with the file system. All commands you type at the shell's prompt are interpreted and executed by the shell.

There are several different shells, and you may not like the default shell. If you'd like to change your shell, type ypchsh. The /usr/bin/chsh program (short for change shell) will display your old shell and ask you for a new one. The preferred method for changing your shell is through the web interface at https://zoo.cs.yale.edu/accounts.html. The list of supported shells in the Zoo includes (but is not limited to):

/bin/tcsh
Tcsh, an enhanced version of the Berkeley UNIX C Shell, csh.

/bin/bash
Bash, the "Bourne Again Shell," which is the standard GNU shell.

/bin/csh
The Berkeley UNIX C shell; considered harmful by some authorities.

/bin/zsh
Zsh, the Z Shell, designed for compatibility with ksh, the Korn Shell.

/bin/sh
The generic Bourne shell. Not recommended.

Setting Up Your Environment

Initially your login environment will have a plain-vanilla setup. You may want to customize your login and logout procedures, your shell, and your window manager. This setup is done by editing certain files in your account, called dot files (because their names begin with a dot (.) character). The default behavior of ls is to ignore dot files, so you may wish to run it with the -a option to have them displayed. Here are a few tips to get you started:

• Most of the dot files for the shells are just a list of commands for the shell to execute when it starts (i.e., when you log in). By customizing these files, you can have your shell perform certain tasks for you automatically. For example, add the line /usr/games/fortune to your .bashrc file (if you're using bash as your shell) to run the fortune program, which prints out a random inspirational / humorous quote, every time you log in. See the documentation for your particular shell for more information on customizing its dot file.
• You can use the "Session" menu on the login screen to specify a window manager (controls the display and management of windows X applications) or a desktop manager (creates a 'desktop') interface -- a trash bin and icons for disk drives, e.g. Desktop managers often include built-in window managers or launch a window manager of your choice).
  • The desktop managers installed on the Zoo include:
    • /usr/bin/gnome-session
      • Gnome
    • /usr/bin/kdeinit
      • KDE
  • The window managers installed on the Zoo include:
    • /usr/bin/sawfish
      • (Sawfish, a lightweight, themeable window manager.
    • /usr/bin/wmaker
      • Window Maker, the official GNUstep window manager.
    • /usr/bin/icewm
      • IceWM, whose goal is speed, simplicity, and not getting in the user's way.
    • /usr/bin/fvwm
      • FVWM, the Fill-in-the-blank-with-whatever-word-you-like-at-the-time Virtual Window Manager.

What Next?

Play around! Try things. It's the best way to learn about the system. Remember that help is always available. (To find out about getting help with the Zoo, visit the Getting Help section of this help system.)