Slide 1: Why Linux?

• It's free AND open source
  • many programmers are developing Linux
  • and they've been doing it for a long time - Linux has roots as far back as ~ 50 years ago
  • Community supported (has pros and cons...)
• It runs on almost any hardware, including older hardware
• It has package managers for almost all system AND application software
  (PMs automate the process of installing, upgrading, configuring, & removing software packages)
• It is designed for central management "from the ground up"
  • Network File System (NFS) is centralized storage
  • "Compute Farms" are centralized computing
• Malware threats in wild: most in Windows, some in Mac OSX, least in Linux

Slide 2: Why Linux? (continued)

• It is very stable (uptimes measured in months or years)
• Gives easy access to all the filesystems and LOTS of computing power
• It has excellent programming environments
  • Excellent scripting tools (bash, python, etc)
  • Many applications/libraries are developed natively for Linux.
  • Linux has a better command line.
  • Package managers
• You learn transferable skills
  • Learning Linux or Unix gives you a strong grounding in the underlying technology that will be useful no matter what products will be fashionable in the future
  • Knowledge of Linux will look good on your resume

Slide 3: Our Quickstart Guide to CLASSE-IT
& Linux at CLASSE page are good starting points

• Quickstart Guide to CLASSE-IT
  (note: CLASSE managed systems ship with the quickstart guide as the Firefox home page)
• Linux at CLASSE

Slide 4: How do I log in?

• Macintosh: ssh; ssh -X or ssh -Y to log in with X forwarding
• Log in from a non-CLASSE network (Red Rover, Time Warner Verizon, At&T, etc)
• Connect To a Linux machine from Windows (VIDEO version 4 minutes)
• note: when you connect to a Linux computer (lnxDDD) from a Mac (mcSSS), Windows PC (pcSSS) or another Linux computer (lnxSSS)
  • your programs run on the destination node (lnxDDD)
  • the running program displays on the source node (mcSSS, pcSSS, lnxSSS)

Login Methods (Overview)

Slide 5: Linux at CLASSE

• General purpose login node: lnx201.classe.cornell.edu
  • This is a shared resource. Please limit its use to brief interactive jobs.
  • Longer jobs should use the compute farm (60 nodes and growing).
    • See https://wiki.classe.cornell.edu/Computing/ComputeFarmIntro
    • Supports interactive use (qrsh) AND batch and parallel use (qsub)
  • Projects and groups have their own dedicated nodes
• All CLASSE Linux systems (including desktops/laptops)
  • have direct NFS access to central storage (500 TB and growing)
  • can run central installations of Matlab, Mathematica, and many other programs
  • https://wiki.classe.cornell.edu/Computing/LinuxIntroduction

• Linux for beginners: https://www.cac.cornell.edu/VW/Linux/

Slide 6: Data Storage

• Three types of information stored on longterm storage (disk, eg)
  • the Operating System (OS)
  • Application Programs
  • YOUR DATA
    • data you want to share
    • data you want to keep long term
    • "scratch" data
• Do not store important files locally! (important files = files you want to share or keep long term)
  • Local disks are not backed up on CLASSE desktop/laptop systems
• Instead, use central storage:
  • Backed up on a regular basis
  • Can be accessed from any CLASSE system: Windows, Linux, or Mac
  • Home directory (1 GB), personal user directory (2 GB)
  • Project space allocated as needed
• At CLASSE, Application Programs and important files are stored centrally; operating system files are stored locally
• Where should I put my files?
  • personal files: UserDisk ( 2GB quota) or HomeDisk (1GB quota)
  • scratch files: (Tem Disk) - /cdat/tem and /cdat/tem2 (Linux); \\samba.classe.cornell.edu\tem and \\samba.classe.cornell.edu\tem2 (Windows)
  • project files: shared by members of a group or project, stored in that project's or group's filesystems (contact your supervisor, project or group leader for locations of your project's filesystems)
  • See https://wiki.classe.cornell.edu/Computing/DataStewardship (with video) for more details

Slide 7: Where are my files?

• Home Disk quota: 1 GB, User Disk quota: 2 GB, Project Disk quota: size of Project Disk filesystem

• From Linux:
  • your Home Disk is available at /home/userid -or- "~"
  • your User Disk is available at /nfs/user/userid
  • 2 examples of Project Space
    • ACCSRF is available at /nfs/acc/srf
    • drafting project space is at /nfs/grp/draft
• From Windows:
  • your Home Disk is available at \\samba.classe.cornell.edu\home\userid
  • your User Disk is available at \\samba.classe.cornell.edu\user\userid
  • 2 examples of Project Space
    • ACCSRF is available at \\samba.classe.cornell.edu\accsrf
    • drafting project space is at \\samba.classe.cornell.edu\draft
  • Type the above addresses into a Windows Explorer address bar.
• From Macintosh:
  • your Home Disk is available at cifs://samba.classe.cornell.edu/home/userid
  • your User Disk is available at cifs://samba.classe.cornell.edu/user/userid
  • 2 examples of Project Space
    • ACCSRF is available at cifs://samba.classe.cornell.edu/accsrf
    • drafting project space is at cifs://samba.classe.cornell.edu/draft
  • From the Finder, click on "Go" and select "Connect to Server", then enter the above addresses in "Server Address".

Slide 8: File Access

Slide 9: Videos, "Cheat Sheet", Tips & Tricks

• Accessing Linux from Windows (4 minute video)
• Linux Beginner, part 2 (26 minute video)
• Linux Beginner, part 3 (19 minute video)
• Linux "Cheat Sheet" (available soon)
• Linux Tips and Tricks (available soon)

Slide 10: Next Session is hands-on with

• SVN
• Matlab & Mathematica
• TeX and LaTeX
• Java in a browser (more likely to work on Linux than on Mac or Windows)
• ANSYS (can serve as back-end)
• apps that you want to install in one place and run from many places
  (for future app requests, please check for a Linux version...)