CSE-376 Lab Facilities (Spring 2017)

Introduction

We have set up limited lab facilities for use by registered class students during the semester. The lab's machines are accessible only remotely and via a secure shell. Details are provided below. Note that the procedures we describe here will be updated and adjusted as needed throughout the semester.

There are restrictions on the use of the Lab facilities:

The lab facilities are limited. Start your homework early! Don't wait until the last minute. The more people compile code all at once, the slower the lab facilities will be. Vary your time of work: some people prefer day-time work, some like to work late at night, some over the weekends. Check who else is on your system (by running /usr/bin/w) and what the load is (using /usr/bin/uptime).

Getting Initial Access

To be able to do your homeworks, you need to do the following three things. Both can be done independently.
  1. First, be sure you have a place to sit and do you work remotely. These days many students prefer to use dorm room computers or personal laptops. You can also use any of the university's SINC sites, as well as the CS department computer labs.
  2. Second, you must subscribe to class mailing list. A lot of useful information will be provided via the mailing list. Through the list, we can distribute information much more quickly to the class students than during the weekly lectures.

    Note: I strongly encourage you to subscribe with your Stony Brook CS account. This will ensure that mail will arrive to you more quickly, and that you are less likely to run out of your mail quota than if you were using some other ISP's mail service. If I post an important message to the class list, and you don't get it because your mail quota has exceeded, I may get a bounce back saying so, but I will have no way to communicate back with you. It is therefore your responsibility to ensure that you can always read the class mailing list and to stay current with what I post there.

    Please do not set your list subscription mode to Digest because digests can take several days to get emailed to you.

  3. Third, you need an account on the OSLAB network. If you are a registered student in this class, your account is already active. You don't need to apply specially for it. (This is a simplification/improvement over past methods.)

  4. Please note that you will get an OSLAB account that will allow you to log into several machines and possibly also a UG lab account. Do not send email to the TA or the instructor from these machines, nor should you expect to get email sent to you on these machines; they are not configured for email processing. Please do all your email communication through whatever email means and email ID you were using outside these labs (e.g., CS's MS Exchange email system). It is particularly important that you follow these instructions to ensure that you could communicate with the teaching staff promptly.

Using the Class Work Machines (OSLAB)

The machines that we set up for your use are as follows. Note that this list will be updated throughout the semester, so check this Web page frequently.

No. Host Name Running Operating System
1a-centos58.cs.stonybrook.eduCentOS 5.8 Linux (i386)
2b-centos59.cs.stonybrook.eduCentOS 5.9 Linux (x86_64)
3b-centos7.cs.stonybrook.eduCentOS 7 Linux (x86_64)
4a-ubuntu104.cs.stonybrook.eduUbuntu 10.04 Linux (i386)
5b-ubuntu104.cs.stonybrook.eduUbuntu 10.04 Linux (x86_64)
6b-ubuntu1604.cs.stonybrook.eduUbuntu 16.04 Linux (x86_64)
7a-freebsd82.cs.stonybrook.eduFreeBSD 8.2 (i386)
8b-freebsd91.cs.stonybrook.eduFreeBSD 9.12 (x86_64)
9b-freebsd11.cs.stonybrook.eduFreeBSD 11 (x86_64)
10a-openindiana5.cs.stonybrook.eduOpenIndiana "Solaris" (build 511, i386)
11a-solaris9.cs.stonybrook.eduSun Solaris 9 (SPARC)
12a-osx.cs.stonybrook.eduMac OS X 10.5 "Leopard" (PPC)
Several more more machines may be added throughout the semester.

To login to one of these machines (say, a-centos58):

ssh -p 130 user@a-centos58.cs.stonybrook.edu
Where user is your username for the account that was given to you on the CS Active Directory (AD) server (your CS AD username is most likely the same as your SBU NetID, but using a different password). If you are using the same username, you can omit the "user@" part. Note you have to use port 130 not the default port 22.

Once you get into your one of the work machines machine, you can start editing source files and compiling as needed. Your home directory is shared using NFS across all of the aforementioned machines.

GIT: Submitting, committing, and backing up your code

This section includes information on how to submit your code via GIT. This is not a comprehensive guide to GIT, so consult the full GIT manual for more help. GIT is a superior Source Control Management (SCM) system than both CVS and Subversion.

Do not wait until the last minute before submission time to figure out how to submit your homework assignment. Learn these procedures well ahead of time, experiment with them, and try and try again. You can submit your assignment as many times as you'd like, but we will consider the last set of files you've submitted as the ones you want us to grade. Don't be late because we won't accept late submission excuses such as "GIT didn't work for me."

Warning: protect your homework from accidental loss! All of the files you have in the virtual machines of this class are not being backed-up. That means that if you remove your files my mistake (happens a lot, often right before a due date), you will lose all of your data and won't have anything to submit. Using GIT you can make a copy of your files and more: record each version of your files as you change them. It is your responsibility to use GIT often. The graders will not accept excuses such as "I just removed all my files and can't submit my homework."
To simplify matters for you we've set up GIT repositories for everyone.
  1. SSH to your VM:
    ssh -p 130 user@a-centos58.cs.stonybrook.edu
    
    where user is your CS AD login name.
  2. Retrieve the your sources via GIT. Each of you have been given a personal GIT repository for each homework assignment.
    git clone ssh://user@scm.cs.stonybrook.edu:130/scm/cse376git-s17/hw1-user
    
    where user (twice in the above command) is your AD username. You'll be prompted for your CS AD password. (Note: the exact URL may be different, so use the one in the actual homework description, if any.)

    The initial checking out (or "cloning") of the git repository will take some time. Using your checked out repository afterward will be faster. Note again that this checkout procedure must be done only once: repeating it can confuse GIT into using recursive repositories, and your homework could be lost.

  3. Next, you can modify any existing source file, then type "make" to compile your changes, install them, and test them.

  4. If you add new files to the repository, you will have to tell GIT to commit them in the repository:
    git add newfile.c
    
    If you have other files to include in your submission, you should "git add" them as well. But, do not submit or add/commit binaries or other object files: those can be produced easily by running "make".

  5. If you wish to create subdirectories under a certain GIT repository, you can do so as follows. For example, to add a subdirectory "test":
    mkdir test
    git add test
    
  6. You can check your uncommitted changes using:
    git diff
    
  7. You can list which files have changed using:
    git status
    
  8. When you are ready to commit changes, you first have to update the GIT index of any changed file:
    git update-index changedfile.c
    
  9. After updating the index of the file, you will have to commit it to your local repository:
    git commit
    
    Be sure to provide a suitably detailed commit message to explain what you did.

  10. Note: at this point, all git did is commit your changes to the local repository only. These changes are NOT safe from VM corruption. To ensure that your changes have made it to the remote (and save) copy on the "scm.cs.stonybrook.edu" machine, you have to "push" the changes:
    git push
    
  11. You can also check what was committed using
    git log | more
    
There are many more GIT commands you could use. Check the documentation online, man pages, and more.

Lastly, you can check out a second, temporary version of your own committed files and verify that they compile and run as you expect them to:

cd ~/tmp
git clone ...
cd hw1-user
git log | more
# configure/test your code, etc.

Last Updated: 2017-01-22