WEB Overview
Written by Scott Ostrander   
Friday, 03 February 2006 05:58

A Guide to the WEB 124 and 130 Instructional Labs

Who to Contact if You Need Help

The "Opers"

Though the WEB 124 and 130 labs are part of the School of Computing, the CADE handles all day to day operations of the labs. During regular hours, you can find help in WEB 130 from the consultants or "opers" manning the lab. Simply approach them on the lab floor or in the office area and request aid. The lab consultants have all the tools needed to keep the machines running properly.

Note: Though the lab consultants may have the technical skill to help you with your course work, this is not their job and they are under no obligation at all to aid you with your course work. If you are having trouble with programming problems during the course of your lab work, contact your TA.

E-Mail assistance through 

If you are working on a machine outside of the lab, or you are working in the lab outside the normal staffed hours, or simply cannot find a consultant in the lab, send your problem via e-mail to . Be sure to include your E-Mail address if mailing from a Web browser.

Your problem will be dealt with as quickly as possible. Should you need to refer to the problem again, please refer using the ticket number you've received.

WEB Instructional Lab Policy


The WEB 124 and 130 Instructional Labs are designed to provide a computing framework for students, staff and faculty engaged in study at the School of Computing.


The WEB instructional labs are open 24/7 unless otherwise noted.


The WEB 124 and 130 labs are equipped with network enabled PC's running Microsoft Windows XP Professional (SP2). The WEB 130 lab also has a user available HP 9150 laser printer, named "ugps".

The installed software on the machines varies from semester to semester and is set by the faculty at the School of Computing. If you feel there is a program that is necessary for your work, please filter the request through your TA.


Acceptable Use Policy:


    • Class work has priority over all other activities. Playing of computer games is never allowed.
    • Your account is for your use only. Do not log other people onto computers using your account.
    • The EMCB instructional labs are quiet areas for study purposes and any use of the PC's producing audio (such as WinAmp) requires a compatible set of headphones.
    • No food or drink is allowed in any School of Computing lab.
    • Use of these machines for mail forging/spamming or harassment of another as well as any illegal purpose (such as unauthorized access of another system/data) is forbidden.
    • Do not lock a lab machine for longer than 10 minutes. The consultants may log you off at any time after 10 minutes. This can cause loss of data!
    • All user files are to be stored on the users "U:" drive. (Files stored on the Windows Desktop or in "My Documents" are located within your U: drive already, under .CS_WIndows.) Your UNIX home directory is the same filespace as the Windows U: drive. Do not store files on the local hard drive. Any and all files on the local drive of any machine may be DELETED without notice.
    • Users are not to install or remove ANY software on these PC's.
    • Print jobs should be limited to 20 pages; no more than 2 copies per print job.
    • EMCB lab facilities and software, as well as this policy may be changed to accommodate future need by departmental staff at any time.

Violations of this policy will result in loss of facility computing privileges!


Using the WEB Labs for SoC class accounts

One consequence of the reduction in SoC computing services is that all class accounts will be handled by the CADE. For most instructors, this has two effects: (1) on-line turning in of class assignments; and (2) establishing accounts for students.

On-line turning in of class assignments

The process in the CADE is similar to the submit facility used within the SoC. 
  • All SoC instructors using the CADE for class support will need an account on the CADE systems. If you do not already have an account or you have an account but have forgotten your password, send email to .
  • While the CADE has a centralized file server, it has no server machines comparable to the SoC trust/antitrust/... To log in to a CADE machine, you need to log in to some individual desktop machine. Hostnames follow the pattern labM-N.eng.utah.edu, where M is the lab number (1-4) and N is the machine number (1-48 for lab1, 1-44 for lab2, 1-25 for lab3, and 1-15 for lab4). While the CADE recomments conntecting to a load-balancing server in order to access the machine which is currently most lightly loaded, this causes problems due to issues with public key encryption. You can avoid the problem by logging in to a specific machine, but then you have no idea in advance of the load or number of other users. Thelab1 and lab4 machines run Linux while the lab2 and lab3 machines run SunOS. Thelab1 and lab4 machines are relatively new dual core boxes and likely to give the best performance.
  • Each class supported by the CADE has an associated user. The user name is csxxxx, where not surprisingly xxxx is the class number. Class related files are kept in the home directory of the class account: ~csxxxx. You will need to establish an account for your class if one does not already exist. You will also need to make sure that your own CADE account has the class group associated with it and that you are the group owner. Once you own the group, you can use the groupmodify command to add your TAs to the group. Send email to requesting establishment of the class user account and class group.
  • Students turn in assignments using the handin program, which is very similar to the SoC submit program. The class directory needs to contain a directory with the name handin, owned by the class account, in the class group, read/write/search for owner and group, and no access otherwise. The handin directory contains subdirectories for each assignment, plus two files: logfile and users.deny. Both of these files need to be in the class group, read/write for owner and group, and no access otherwise. Because of the need for the class account to own these files, you may need to request that the be set up by sending email to . More information on the CADE handin system can be found by typing the following while logged in to a CADE machine:
man handin
man rcvhandin
  • scp -r ... can be used to copy handin subdirectories from the CADE to the CS system, which is usually easiest for grading.

Example of how to establish a CADE handin account

To enable handin, cd to the class handin dir, e.g.,:

% cd ~csxxxx/handin

You can increase the chances that all files created in this directory will be in the correct group by insuring that the setgid bit is on for group:

% chmod g+s ~csxxxx/handin

Make sure an empty file named users.deny exists:

% touch users.deny
% chmod ug=rw,o= users.deny

This file tells the handin program who not to allow to handin files. Since it will be empty, there will be no restrictions on who can submit material. 

Now create a directory for each assignment and again copy the users.deny file into the new directory:

% mkdir Assignment1
% chmod 
ug=rwx,o= Assignment1
% cp users.deny Assignment1
% chmod 
ug+rw Assignment1/users.deny

You can also create a .comment file in the assignment directory. The contents of this file will be shown when the student types:

% handin csxxxx

with no additional arguments.

Make sure you test that all is working by trying to handin something yourself!!!

Establishing CADE accounts for students

At the start of every semester, the CADE will obtain a list of students registered in each class having a CADE class account. Accounts will be created for anyone on that list who does not already have an account. A hard copy listing of real-name/user-name/password can get picked up from one of the CADE operators a few days before the start of each semester. This list is designed to be cut up and handed out to the individual students. Any student that is officially registered but does not have an existing CADE account and is not on the CADE-provided list will need to see one of the CADE operators in EMCB. For upper division undergraduate CS classes, most/all registered students will alreay have CADE accounts.

Turning in files using handin in the CADE

To electronically submit files while logged in to a CADE machine, use:

% handin csxxxx assignment_name file_1 file_2 ...

where csxxxx is the name of the class account, and assignment_name is the name of the appropriate subdirectory in the handin directory.

The CADE also provides a web-based facility for turning in files electronically: <https://cgi.eng.utah.edu/webhandin/index.cgi>