Introduction

The Operations Research Department operates an integrated PC/workstation network system to meet the computing needs of its faculty, staff and students. This document gives a description of the computing facilities available for students at the OR department, as well as the policies and procedures for their use. All OR graduate students are given a userid for the local workstation network. The workstations host a variety of public domain and department-licensed software that run in the UNIX environment. Your UNC Onyen account gives you access to these programs, as well as to UNC resources and the Internet. You can connect to the network from PCs and workstations in the student labs in Smith 206/207, PCs in Smith Building that are connected to the network, or remotely from any machine with a modem or network connection.

Computer Lab Coordinator

Wang Zhohui Office: 310 Snith Office Hours: 3:30 PM - 4:30 PM Mon to Fri. E-mail: wangzh@email.unc.edu

Wang Zhohui helps maintain the Computer Labs in Smith 206 and 207. His primary responsibility is to ensure that the PCs are in operating condition for both PC applications and network connectivity. Report any problems you may encounter with the PCs, including printing, right away to expedite his attempts to solve them. He can best be reached by e-mail if he's not in the building.

Zhohui will summarily delete any unauthorized files installed on the PCs and periodically remove files in the user directory to free up disk space. He will deal with minor unix issues and relegate the major ones to the CC and Network Administrator. Occasionally, he will send out e-mail that you should read if you want to be kept updated on the state of the Department computer ystem.

Computer Faculty Coordinator

Professor Scott Provan
Office: Smith 213
E-mail: provan@email.unc.edu

Dr. Provan is the second line of defense for major unix issues; if he can't fix them he will refer them to the Network Administrator, together with an assigned priority. He is also the department Web Information Coordinator.

Network Administrators

ATN Unix Desktop Support:
Office: Abernathy 121
E-mail: uds@unc.edu

Arts and Sciences Information Services (PC support):
Office: Hamilton 372
E-mail: anna@unc.edu
Service requests via the web

These are college wide support groups. You should direct all but the most critical problems to the departmental personnel. (Crashing one of the UNIX compute servers is a good example of a critical UNIX problem.)

Department Secretary

Barbara Meadows
Office: Smith 210
E-mail: bmeadows@email.unc.edu

Let Barbara know if the printer is low on toner. Also report to her problems with the heating or air conditioner. (Students are responsible for their own paper.)

General Assistance

The best assistance is that of experienced fellow students. If you have questions about PC operation, e-mail, or the university network that the local folks cannot answer, you can call the UNC Help Desk at 962-HELP.

The Computer Lab

The OR Department Computer Lab in Smith 206/207 is a continually evolving system of workstations, PCs and printers. The Computer Lab is for Department graduate students and faculty use only, and others with special permission. As of this writing, there are two Sparc IPX workstations running Solaris (SunOS 5.6), about eight IBM PCs, two Dells, and an HP LaserJet PostScript printer. The PCs all run Windows NT and are connected to the university network. All of the lab computers are connected to the university network and the Andrews File System (AFS). There are also some Dells and Gateways in student offices on the 3rd floor; these machines remain the property of the Department but maintenance and troubleshooting are the responsibility of the students themselves.

Student Accounts

Students accounts give them access to PC and Unix sytems, e-mail, AFS directories (see below), and the available departmental and university software applications. Please keep your accounts secure by keeping your password private. This will save us from the serious problem of hacking that has plagued other departments. To change your password, email defaults, and check your mail and home directory storage availability, go to the ONYEN page.

Your account will be closed one semester after you leave the Department, so be sure to remove relevant files when you graduate. Student accounts may be extended if special circumstances warrant it.

The AFS File Storage System

The Andrews File System (AFS) is a universal file storage system used by the university. Students, faculty/staff, and the department have file space on this system, and it is accessible from both PC and Unix environments. Files are kept in duplicate and backed up overnight. Upon PC login, students have their own file storage (under their H: drive) with 20M of personal and e-mail storage. The department space is contained in the I: drive, and the university network is listed under the J: drive. Upon login to unix the the home directory is the default directory, and the departmental directory can be reached as /afs/isis/depts/or.

Save all of your work in your AFS home directory. Do not save material on the computer drive itself, as this will be periodically cleaned by the lab assistant. Thesubdirectory Student Files is available for temporary storage on each computer.

Your home directory also has an Oldfiles subdirectory which contains yesterday's copies of your files, in case you accidentally delete or mutilate them. Files from further back can be obtained by e-mailing webmaster@unc.edu and giving the date and path to the file.

Warning: Do not remove any subdirectories or files that are in your initial AFS home directory, as these hold key unix defaults, web pages, and other important functions.

Sun Workstations

The Sun workstation seymour (seymour.or.unc.edu) resides in Smith 206 and is for students who want a workstation terminal access. All PCs also have complete access to seymour. Simply click on XSession and SecureCRT, and log into the appropriate machine (seymour is the default). This establishes a full X-windows session with the workstation. More on workstations below.

Available PC software

The following software is loaded on the PCs in Smith 207:

• XWin-Pro: X-windows environment/workstation network link
• Microsoft Word: Office 97 word processing package
• Microsoft Excel: Office 97 spreadsheet package
• Microsoft PowerPoint: Office 97 presentation graphics package
• Mathematica, Maple: mathematical computing environment
• Matlab: matrix computing environment
• IDEAS: OR instructional software
• PCTeX32: text processing software LaTeX2e (some machines)
• Netscape Communicator & Internet Explorer: web browsers
• Netscape & Mulberry: Mail program
• Ghostview and Adobe Reader: for reading .eps (PostScript) and .pdf
• Arena and ProMod: simulation packages
• LINDO: linear programming software

Computer Room Protocol

Log out at the end of every session. This can be done by Start-Shutdown-Close all programs and log on as a different user. For unix logouts, make sure there are no applications still running, as they can continue and clog up the system.

Although the software on these machines is fairly tamper-proof, do not attempt to circumvent the normal operation of the software or operating systems. This can cause unforseen problems far into the future.

Although your home directory on AFS is the safest way to store your files, you may also use the local D: drives to store material, by making a directory for yourself, giving it your name for easy identification, and storing your files there. Files that don't clearly belong to anyone will be deleted by the CLC. You will be notified in advance if it is necessary to remove files in the D: directory to make more space.

The order in which to reset frozen processes is generally:

1. Use the applications software to kill frozen processes or correct glitches.
2. Use the NT Task Manager to shut down windows that are not responding.
3. Log out and log back in.
4. Reboot (shut down and restart).
5. Turn the machine off and back on.

Do not turn off the PCs in Smith 207 unless there is a problem, since they take a long time to reboot. If you must turn the machine off, try to use the Start-Shutdown route before turning off the computer.

Never, under any circumstances, should you shut off the workstation. It is handling many users and services on a continuous basis. Only authorized personnel should shut down this machine. You can effectively kill any frozen workstation application remotely (see Workstations below).

Do not play games, cruise/surf the "leisurenet" or send personal e-mail while the computer lab is busy.

Close and lock the lab room door if you are the last person to leave.

Do not remove manuals from the labs.

Record problems with the computers on the maintenance log in Smith 207. (The better a problem is documented, the easier it will be to diagnose and fix.)

Keep the computer lab neat. Put manuals away when you are finished and dispose of all paper and other trash in the appropriate receptacles. Smith 207 has been known to harbor viruses if it is not kept clean.

Printing

The default printer for both the PCs and workstations is the one in Smith 207 (unix network name hp5m). It has postscript capabilities, and works with all software.

Do not turn off the printer unless there is a problem. This is also the network printer and other users may be sending print jobs remotely. If you need to cancel a print job that has already been sent to the printer, try pushing the "cancel" button first. You can also cancel unix jobs from your terminal by typing lpq to display the job number, and then entering cancel .

You are responsible for providing your own paper for the printers.

If you are printing remotely, make sure you have your own paper in the printer. If you run out of paper in the middle of a print job, either add more paper or cancel the job. Do not leave it queued up on the printer.

Computers in Student Offices

Student offices in the 3rd floor are wired into the network and all of them should have at least one network-capable PC. If you have a PC with an ethernet card, check with the Computer Coordinator, and we can try to get you connected (if there are enough ports). Software and maintenance of the 3rd floor computers are entirely up to the students.

E-mail

Your university e-mail address is @email.unc.edu. Their are several ways to use e-mail:

Mulberry: a convenient mailer that can be started from the Mulberry icon on the PC desktop. There are convenient menus and help material.

Pine: the e-mail tool of choice, and useable from workstations and any remote terminal login. To get pine from the PCs, use SecureCRT to log on to isis.unc.edu, and then choose Electronic Mail (or from a departmental workstation enter pine at the UNIX command prompt). Pine is easy to use and menu driven, with command choices listed at the bottom of each screen.

Webmail: This is a convenient web-based mailer available from ATN. The web address is http://webmail.unc.edu. It is a little slow and has its limitations.

Netscape mailer: This is the most convenient for a personal PC hookup, and can be run any time you have a Netscape link to UNC, but it is a pain to set up from a public machine. For details on personal hook-up, see the ATN page on Internet Service Providers.

For mass mailings, the following aliases have been set up on the campus mail server: orfaculty, orstaff, orstudents, and oralumni. Please avoid sending junk mail. If you are replying to a mass mailing and there is no need to advertise your response to everyone else on the list, just say no to the ``reply to all recipients'' prompt.

Check your e-mail periodically as almost all OR Department announcements are made via e-mail. Whenever possible, use the PCs connected to the ethernet on the 3rd floor student offices to check e-mail. When the computer lab is busy, do not use the PCs or workstations in Smith 206/207 for personal e-mail.

Remote Login to University Systems:

You may read your mail and log onto the department's workstations remotely. Remote logins cannot be done directly to the department's workstations, but must be done through the university server, isis.unc.edu. E-mail and files from your home directories can be obtained directly from isis, and the department workstations can be accessed from this using the ssh command. The standard FTP software (Ws_ftp is available by download from ATN shareware) will also allow you to download and work on any files in your home directory.

If at all possible, use a secure remote login to the workstations. For PCs, this is done using SecureCRT, and from the workstations it is done using the ssh command. Try not to use telnet or rlogin.

Library Card Catalog

The library catalogue can be accessed directly from the web

File Maintenance and Editing

File editing and maintenance is best done through the PCs, although Unix-comfortable users can certainly use the workstation editing and file-management facilities. If necessary, straight ASCII editors are available on the PCs (Start-Programs-Accessories-Wordpad is a good one). Most applications work just as well after either PC or Unix editing, so sometimes it is most convenient to edit in the PC side and operate on the Unix side. Remember that both sides are looking at the same file system. (The two systems treat carriage returns a little differently, so if you don't want ^M symbols on your unix file end-of-lines, it is best to restrict your editing to one system.)

Changing File/Subirectory Permissions

The read-write-list permissions for a file/subdirectory are determined by the AFS status of the file/subdirectory. The AFS read-only status for a file can be seen by right-clicking on that file and choosing Properties. File permissions can be changed by clicking on the Read-only box. AFS directory permissions are more elaborate, and can be seen by right clicking on the directory, choosing AFS, and choosing Access Control Lists. This will give all users that have access to your subdirectory, and how much they can do. If you want to add a user, click on Add and add that user. If you want to change permissions of a user, choose the relevant user, change the permissions by clicking on the appropriate squares, and then clicking OK. This will not change permissions of subdirectories of that directory; if you have subdirectories you will have to go to each of the subdirectories individually and change permissions. AFS file permissions supercede unix permissions. Thus the unix ls command may give incorrect file permissions, and cause confusing results for unix users. Always check/reset the AFS permissions if you get a file read-write error.

Workstations

The departmental workstations - seymour.or.unc.edu and tucker.or.unc.edu - are available to the students. These are both SUN Ultra80 model 2450s, with 450 MHz dual processors, 1GB RAM memory and 18G internal drive. They are accessible from all of the lab PCs, with seymour the default. Please use seymour under normal circumstances.

If you lose control of your workstation session, you can remotely kill your own session, by logging on to the frozen machine from, say, a PC, using ps to determine the number of the Xsession, and using kill to kill the session..

Your storage space on the workstation is the same AFS space that is available from the PCs. Again, you have a 20M limit.

Using Unix

UNIX is the operating system of the department's workstation network, and the kernel is Solaris (SunOS 5.6). UNIX terminals have a command line interface: you enter commands at the prompt, and the C-shell interpreter parses your commands. UNIX is case sensitive and there's practically no restrictions on file names. Here is a summary of useful commands:

• ls: list directory contents
• pwd: display present working directory
• cd: change directory
• mkdir: make directory
• rmdir: remove directory
• rm: delete file
• cp: copy file
• mv: move or rename file
• lpr: print file to default printer
• man: access help pages
• |more: to display one screen at a time

There is also a wildcard (e.g. ls or*.dat |more lists files and directories whose names begin with the letters `or' and have the extension `dat' one screen at a time).

Available Unix Software

• Cplex/AMPL: mixed integer optimizer/and LP development tool
• LaTeX: text processing software (LaTeX2E)
• Mathematica: symbolic computing environment
• Matlab: matrix computing environment
• Simscript: simulation software
• Netscape: web browser

SAS and other similar packages are available on the statistical applications server statapps.unc.edu

Unix Graphics Capabilities from PCs

All PCs have full graphics capabilities when logging on to a workstation; if you don't, you probably forgot to start an XSession before using SecureCRT. To get graphics capabilities from a terminal login, you may need to disable server access control and redirect the output. For example, to run mathematica on seymour from tucker, you could enter the following commands:

• tucker% xhost +
• tucker% ssh tucker.or.unc.edu
• seymour% setenv DISPLAY tucker.or.unc.edu:0.0} \\
• seymour% mathematica

Further Information Available on the Web

Much of the departmental information (e.g., this page) will be available solely on the web. The departmental web site is www.or.unc.edu. Look under various listings for course information, schedules, colloquia, news, links to other interesting stuff, etc. There is also a lot of useful information you can find starting from the University web page; for specific computer support, check the ATN ``Virtual Help Desk'' or the old-fashioned way at 962-HELP. Surfing the Web has absolutely no priority over any computing activity. You may not install any programs downloaded from the Web, including utilities, Web browser plug-ins and games.

You can make personal web pages if you know HTML; see the University's how-to page for details. The URL for your home page is www.unc.edu/~< userid>. The Computer Coordinator can set up a link from the Department web page, if there is not already one in place.