introduction to athena
TRANSCRIPT
Introduction to Athena
Jonathan Reed
Information Services & Technology
2013 Edition
What is Athena? • Campus-wide Linux computing environment
• File storage & websites
– both personal and group
• Instant messaging
• Printing infrastructure
• Academic software
Debathena • Software that powers Athena
• Provides Athena services and environment on Ubuntu Linux and Debian Linux
• http://debathena.mit.edu
Where is Athena?
• Public computing labs (“clusters”) around campus
– See Computing@MIT: The Map or IS&T website for locations
– Combo: 37619
• Quickstations
– For short 10-minute login sessions
• Dorm clusters
• Department computing labs
• Athena remote login ("dialup”) servers
• Your own PC, with Debathena installed
Athena Clusters
Group Work Spaces
Laptop Stations
Scanning Stations
Cluster Rules
• No messy food; covered beverages OK
– “If you spill something, say something.”
• No cellphones, music, or loud conversations
• Activate the screensaver if you need to leave the cluster briefly; after 20 minutes, you can be logged out if the cluster is full
• Clean up after yourself
– Recycle paper whenever possible
• Equipment broken/not working?
– Email [email protected]
Your Athena username
• Also called your Kerberos principal
• Your e-mail address without the @mit.edu part
• Cannot be changed
– Can pick mailing list as alias e.g. [email protected] -> [email protected]
• May be different from departmental username
Your Kerberos password
• Used to log in to Athena, check e-mail
• Can (and should) be changed frequently
– Once a term is a good guideline
• $ passwd • http://mit.edu/password
• Don't use the same password for any other account or website
• Don't share your password with others
• Must be changed every 365 days
Password Guidelines
• Always use a strong password
boyfriend/girlfriend's name
• If you store your passwords on your computer, use an encrypted password vault (e.g. LastPass)
• Athena requires a password to log in and to disable the screensaver
• Do the same on your laptop
combination of letters, numbers, punctuation, and symbols; or phrases
Athena Login Screen
© Diez Photography, CC-BY 2.0
Logging In
• Enter your username, and press Enter
• Other session types:
– "Athena TTY (Terminal) Session"
– ”Repair My Account” (available in Sept)
Your Login Environment
Launcher
• Lens ("Start Menu")
• Home directory
• Firefox
• LibreOffice Writer ("Word")
• LibreOffice Excel ("Excel")
• LibreOffice Impress ("PowerPoint")
• Software Center
• System Settings
• Trash
• Workspaces
• Current application (Terminal)
Launcher
• White triangles on the left indicate the active application; triangles on the right indicate the number of open windows
• Right-click on launcher icons to open applications or perform other actions
– "Lock" items to launcher to keep them there.
– "Unlock" to remove them.
– Click and hold, then drag to re-arrange
Launcher
• The Lens (Ubuntu logo) lets you launch other programs
• Click, and begin typing the name of the program, then select the program you want from the resulting list
Launcher
• At the bottom of the lens window, you can browse various file types, including applications
Logging Out • Always log out
• "Log Out" from the power menu
• or logout in the Terminal
The Screensaver
• Lock your screen when you step away
• Unlock when you return
• "Log Out" button will appear after 20 minutes of idle time
Menubars
• Name at top left of screen indicates active application
• Menubars are shared across all applications, at the top of the screen
• …but they're hidden until you move the mouse to the top of the window
File Management
• "Go" menu
– Access home folder and other folders
• Or "Home" folder in launcher
Nautilus File Browser
Kerberos
• Your password is used to obtain ‘tickets’, which are in turn used to identify you to various services
• Tickets last 10 hours, at which point they must be renewed
– "Renew Authentication" from the Launcher
– or use the Terminal $ renew
AFS • Your personal home directory:
– /mit/joeuser
• 2 GB quota (can be increased)
• Default subdirectories
– Private, Public, www
• Automatically backed up
– “OldFiles” is a nightly read-only snapshot
• Lockers: collections of files
– Home directories, student groups, courses, etc
Permissions in AFS • All permissions are on a per-directory basis, not per-file
– The chmod command will not work the way it does on other UNIX/Linux systems you may have used
– 7 rights (rlidwka) instead of the usual 3 (rwx)
• View and set AFS permissions with the fs command (in the Terminal) or using the file manager (as shown on next slide)
• More info: http://ist.mit.edu/services/athena/afs
Modifying Permissions in AFS
• Right-click on a folder, choose Properties
• If the folder is located in AFS, the AFS Permissions tab will appear
Your web space
• /mit/username/www • Accessible at http://web.mit.edu/username/www/
• Do not violate copyright laws or harass others
• Suitable for hosting basic websites and media
• Use SIPB’s Scripts service to create dynamic content (blogs, wikis, webapps, etc)
– http://scripts.mit.edu – works with your Athena account
• Can also set up a redirect to your existing website
Zephyr
• Instant messaging at MIT
• Get notifications of cluster closings or service outages
• See if your friends are logged in
• $ zlocate janeuser
• Get notified when your friends log in and out
• $ gedit ~/.anyone
• Add your friends’ usernames to this file, one per line
• $ znol
Zephyr examples
• What you type:
• What they see:
$ zwrite joeuser Type your message now. End with control-D or a dot on a line by itself. Hi there. . Message queued for joeuser... sent
Jabber • Chat with MIT users and other Jabber users (Gmail Chat)
• Use the Pidgin client
Jabber • Your Jabber ID is
– Account automatically configured in Pidgin
• Buddies must authorize each other in order to see their login status
• The Pidgin client can also be used for AOL (AIM), ICQ, MSN Messaging, IRC, and Yahoo chat
– Select Manage Accounts from the Accounts menu
Printing
• High-capacity laser printers in every cluster
• All dorms have at least one printer
– Color printer in W20-575
• 3000 pages/year print quota
– Check your quota online http://techcash.mit.edu
• Print to printer named mitprint or mitprint-color
• Pick up job at any release station using MIT ID card
© 2009, Pharos Systems
Remote Access to Athena
• Athena "dialup" servers
– athena.dialup.mit.edu is a load balancer directing you to the server with the least load
– Gets you an Athena prompt like your Terminal window
• Connect using SCP, SFTP, or Kerberized FTP for file transfer
• Connect using SSH for login sessions
– With optional X11 forwarding for running graphical applications (e.g. MATLAB, Maple)
• SSH/SFTP and X11 software for Windows/Mac available on IS&T website
Transferring Files to/from AFS
• Secure FTP clients
– Windows: SecureFX
– Mac OS X: Fetch
• Recordable CDs and DVDs
– Insert a blank disc to launch CD/DVD creator
• Public files can be downloaded via the web
• USB flash drives (“thumb drives”)
Install any software you need
• Cluster workstations give you root privileges
– Become root using the sudo -i command
– Or tellme root for the root password
• This means you can install any applications you need for the duration of your login session
• Install anything in the Ubuntu package repository
– Choose Ubuntu Software Center from the Launcher
– Current Linux users: • sudo apt-get install packagename
Help with Athena • Web-based tutorials
– http://ist.mit.edu/services/athena/olh – Introduction to the Command Line – Introduction to AFS
• Answers to common questions
– http://kb.mit.edu
• SIPB Wiki – http://sipb.mit.edu/doc
Getting Help • In person:
– E17-110: Mon-Fri, 9:15am - 5pm
• By phone & e-mail:
– [email protected] 617-253-1101 Mon-Fri, 8am - 6pm (Tue. until 5pm)
• Networking help in your dorm
– http://rcc.mit.edu
• Online, anytime:
– http://kb.mit.edu
– http://ist.mit.edu