Hall computer how-to

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Simpi: Debian-Athena workstation in KL

Piwest: Debian-Athena server in TVL

People to ask for help

meeg has the power (e.g. root). There are also many Linux-savvy people around who can help you with the things covered here.

When things go wrong

Never restart piwest. If you think a reboot is necessary, ask meeg.

Simpi does not mind being rebooted, but people may be logged in remotely. Check who is logged in (`who' command) before you reboot. Use Ctrl+Alt+Delete from a console (preferred) or press the reset button.

Ctrl+Alt+Backspace will restart X, killing any X logins.

Consoles and X

Black screen with white text: console (tty1 through tty6).

Colors and graphics: X (tty7)

Switch between with Ctrl+Alt+F1-7.

Remote login

From a computer with a command-line SSH client (a Linux or OS X machine):

ssh meeg@piwest.mit.edu

(substitute your own username; can also substitute simpi for piwest)

From an Athena machine:

ssh -K piwest.mit.edu

(-K option passes Kerberos credentials from one computer to another)

From a Windows computer, use PuTTY (recommended by us) or SecureCRT (recommended by IS&T).

You need to be on the third-west list to log in remotely; if you get e-mail from floorpi, you're okay. Because of the way Debathena machines check group membership, this may not work if you are in too many AFS groups. You don't need to know what this means - just be aware that if you're on too many mailing lists and you can't SSH to simpi or piwest, you may need to ask meeg to add you to the access list manually.

Useful commands

• man [command] (looks up the manual entry on some command)
• who (tells you who is logged in)
• uptime (how long the computer has been running)
• date (what day and time is it now)
• screen (useful commandline terminal extension thing to infinite!!!)
• write (send a message to another user logged in, use `zwrite' across Athena)
• ssh (login remotely to another machine)

These require special permissions:

• mplayer (plays back most audio formats)
• alsamixer (volume control)
• ncmpc (mysterious music playback daemon with playlist)
• sshfs (attach a remote filesystem to a local mountpoint, persists until machine is rebooted)
• smbmount (equivalent of sshfs for Windows fileshares)

Workstation quirks

The Debathena workstation environment (as seen on simpi) is somewhat different from regular Athena (as seen in clusters). Tips:

• Firefox is called Iceweasel and is in Applications/Internet.
• Terminal is in Applications/Accessories.
• Log out from the System menu.

Sound system

Simpi has a set of speakers connected directly.

Piwest has multiple outputs:

• Front: CD channel on TVL receiver
• Surround: unused
• Center: Munroe bathroom
• LFE: Kitchen and KL