Getting Started

Introduction

Welcome to computing under Unix at UMBC. Whether you are a novice at computing or simply new to Unix, it is hoped you will find this document helpful. Keep in mind that there are literally thousands of volumes available which explain every detail of Unix---user guides, reference manuals, textbooks and the like, as well as countless other publications from the most user-friendly to the most technically complex. Obviously, therefore, this brief handbook can make no attempt to be comprehensive. What it does try to do is to get you started, and to point you in the direction of more information should your needs so dictate. And since the aim of this material is also to ground you specifically in Unix as found at UMBC, you will find sections on local resources, conventions and facilities as well. For many users, then, UNIX AT UMBC may suffice as a stand-alone orientation to academic computing on campus.

Some Conventions Used by this Guide

Unix Hardware and Software

Office of Information Technology offers a number of Unix-based systems for use by faculty and students. The unified computing environment encompasses our SGI Irix, Linux, and Solaris Unix services. All members of the UMBC community have access to the UCE for the following services: authentication through Kerberos, common file service through AFS, Web serving, and basic interactive logins.

Some Unix resources are not for general use and support specific user groups. The machine known as Titan is the newest addition to the campus complement of Unix resources; TITAN is a Silicon Graphics Power Challenge-XL, a 20-processor system with a processing power of more than 300 MIPS (millions of instructions per second) and a floating point capacity of more than 120 MFLOPS (millions of floating point operations) per processor. The machine includes two gigabytes of RAM and 70 gigabytes of user disk space. It can be expanded to support up to 32 processors and more than 4 gigabytes of RAM. In addition, future upgrades can provide the ability of tripling the floating point capability of the machine. TITAN is chiefly employed for faculty research and is the campus's primary compute server.

UMBC7, another SGI machine, serves as an additional resource for faculty and staff. A Challenge XL with 12 processors, each processor rated at 120 MIPS and 40 MFLOPS, UMBC7 is equipped with 756 megabytes of RAM and 40 gigabytes of disk storage space.

OIT maintains a wide range of software resources, information is available at the URL: http://www.gl.umbc.edu/environments.shtml

Computing Facilities

Office of Information Technology's facilities are concentrated in the campus' Engineering/Computer Science building. There are SGIs located in ECS 021 for general use. Additionally, room 104a contains SGI O2 workstations with enhanced graphics capabilities; this area may be reserved for instruction and access by students taking courses in ECS 104a. ECS 021 does have general walk up Unix workstations and PCs which can be booted into Red Hat Linux or Windows 2000.

OIT microcomputer laboratories in the ECS building are equipped with PC's running Windows 2000 and Macintosh machines, all of which are capable of connecting to the Unix systems. Both NT and Macintosh machines have access to the campus AFS servers for common file access. There are also special instructional and faculty-only areas; for more information call the Help Desk at ext. 53838.

Printout operations have been consolidated in one location, ECS room 019, which contains laser printers. Laser printers connected to the campus network can also be found in a number of academic departments, although access to many of these devices is restricted.

During the spring and fall semesters Office of Information Technology maintains extended "open" hours, with twenty-four-hour service in effect for much of this time. Exact schedules are posted prominently. On-campus residence halls and apartments have ethernet connections with which to connect to the campus network through Resnet. Off-campus dial up users who have access to computers with modem connections may dial up at any time from off-campus locations, providing system maintenance is not taking place.

Getting An Account

OIT has automated the accounts generation process to provide quick turnaround time for all users. Accounts provide access to myUMBC, AFS, the Unix machines together with the SGI workstations, and all Win2000 and Macintosh workstations. They are available to all classes of users--undergraduate and graduate students, staff members and faculty.

Student accounts are validated against the campus enrollment database, while faculty and staff accounts are validated against the campus personnel database. It is possible, and in fact likely, that entries for some people will be missing from one of these databases. This could occur because they were enrolled or became employed after receipt of the data. While timely updates of these data files are obtained, the files cannot be totally current. If you encounter problems registering for an account please go to ECS room 020. A Helpdesk employee will assist you in resolving your problem.

To register for an account, a student, faculty or staff member can go to the Accounts webpage. You will need to provide your Social Security Number, and your PIN, which is defaultly set to the MMDD of your birthdate. You should then choose a username, and read and agree to the University Computing Policy, and choose a password.

Maintaining the Security of Your Account

You are responsible for the use of your account and the contents of your files. Guard against intrusion by choosing a secure password and changing it at frequent intervals thereafter.

Irresponsible behavior such as practical joking or malicious use of the computer will not be tolerated, nor will annoying other users with unwanted messages or foul language. Moreover, obtaining or changing information maintained in someone else's account without permission is not only unethical, but is also a violation of State and federal law which is punishable by imprisonment and/or fine. If you believe that you are a victim of abuse of this type, contact a staff member immediately.

Getting Help

Where To Ask

Questions may be directed to the student consultants working the Helpdesk in ECS room 020. All UMBC computer users are eligible for this service. For computer science help, please go to the Computer Science Helpdesk in ECS 332. However, the logical construction and writing of student programs, debugging, etc., remain the responsibility of the user.

Students having difficulty in understanding their course work or assignments may want to seek the assistance of a Learning Resources Center tutor. Call ext. 52444 to contact the LRC about its tutoring services. Computer Science majors may also consult the special tutors provided by the CS department.

Assistance on software or hardware questions is available by calling the Help Desk at ext. 53838.

Where to Get More Documentation

Readers needing more complete documentation than can be provided in an introductory guide such as this have several choices.

Office of Information Technology maintains a complete set of Unix reference manuals, and its technical library contains a copy of the reference manual or user guide for each software package installed on the systems. Inquire at the Helpdesk, ECS 020. Those in need of frequent access to detailed documentation may want to purchase individual volumes through the campus Bookstore. Additionally, Insight, an SGI software product, offers detailed on-line help on each SGI application running on the system.

For help on individual commands, the Unix system includes its own on-line reference manual pages, which are electronic versions of those available on paper. Since they mirror paper manual entries, these on-line references are called "man pages." The Unix command man displays manual pages on your screen. To look at the manual page for the man command itself, enter

man man 

"How-To" Short Courses

Connecting to Unix

To gain access to your system, you must identify yourself as an authorized user. This is accomplished by logging in. Once connected, you can proceed with your work session.

Furthermore, not every user will connect to Unix in the same manner, as this process is determined by your physical location, your type of hardware and type of connection. If you are connecting to an individual workstation in a lab, the process is simplest. Members of the UMBC community with home computers may wish to call the Help Desk at ext. 53838 to learn more about their options.

Logging in to an SGI Lab Workstation

If you are working in one of University Computing's SGI labs in the ECS building, your screen will display a centered login area. This displays the prompt

Login:

Type in your Unix username, making sure that you use lower case letters. Press <RETURN>. The next prompt is for your password. Enter this exactly as it was given to you, noting that what you type will not display or "echo" on the screen. This is a security measure---Unix will interpret the keystrokes regardless. Press <RETURN> again. (If you have trouble logging in, ask the student consultant on duty for assistance.) Once you have entered your username and password correctly, you will see some introductory messages, and then you will get the workstation's system prompt, which will look something like

umbc8[1]%

At this point you may begin to enter Unix commands. You may wish to work locally at the lab workstation, or you may decide to use your machine's ability to reach a multi-user node such as GL.

Logging in from a Microcomputer with a High-Speed Ethernet Connection

If you are using an on-campus microcomputer to connect to a Unix node, you will need some sort of physical link to the campus network, and you will also need software to transform your micro, temporarily, of course, into a "terminal" so that it can interact with one of the multi-user Unix systems. All campus micros, and all of those in the OIT microcomputer labs, make this transformation through a high-speed Ethernet link.

Logging in from Your Office Unix Workstation

If you have a workstation in your personal work area, it undoubtedly is Ethernet-connected. Thus you need only run the telnet program to connect to one of the multi-user Unix nodes, as in telnet UMBC7. Since both your machine and the campus Unix systems share the same domain (UMBC.EDU), it is not necessary to include it with this command.

Logging in by Dialing Up

For information on connecting to UMBC through the UMBC modem banks, please refer to our PPP documentation, http://www.umbc.edu/oit/pc_ppp .

If You Have Problems Logging In

If you have not entered your account username and password correctly, your Unix machine will respond with a "login incorrect" message. Another login: prompt will be displayed so that you may try again. If after three attempts you still have not succeeded in logging in you should locate the student consultant, who will determine what steps are needed to resolve your problem.

Changing Your Password

When you have received the system prompt you can begin entering commands. The very first command you should enter is the one that changes your password. The solution, of course, is to change your password to something you can remember, but not to something obvious such as your first name. To authenticate logins, OIT employs the kerberos program on all of its Unix machines.

At the system prompt type in the passwd command to change your password:

umbc7.umbc.edu> passwd

Press <RETURN>. The system will respond

Old password for <username> (where <username> is your own username)

Type in your current password. As when you logged in, this will not be displayed as you type. Press <RETURN>. You will then see

New password for <username>:

Select your new password, choosing at least six characters, and type it in. Press <RETURN>. The next prompt is

Verifying, please re-enter new password for <username>:

Re-enter your new password and press <RETURN>. Assuming the machine has accepted your new password you will receive the message

Password changed

If the system has not accepted your new password (too few characters, for instance) it will display

Password unchanged

Try again. If you experience continued problems see the student consultant.

Logging Out

When you have completed your work on the computer it is important that you log off. Switching off the machine or hanging up the phone will not accomplish this, and in fact, will simply leave your work vulnerable to the whims of anyone who might switch it back on again. To log out, enter the command

exit

and press <RETURN>. (Some systems will also accept logout or (CTRL/d.)