The UNIX® CRONicle

May 1999

Official Publication of the STL!/unix/usr/group

UNIX® is a registered trademark of the Open Group
Linux® is a registered trademark of Linus Torvalds
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Table of Contents

Next Meeting Details

Wednesday, May 12, 1999 at 6:30 PM
Sunnen Products, 7910 Manchester

6:30 PM Tutorial The Password File by Mike Kriz
7:00 PM Call For Help (An opportunity for you to ask technical questions of the group)

7:15 PM Social, off-line conversations, & book sales

7:20 PM Admittance to building may no longer be possible See Meeting Directions

7:30 PM Presentation NFS, NIS, and Core UNIX Services by Dave Dickerson


NFS, NIS, and Core UNIX Services by Dave Dickerson


What are they, and what can you make them do for you?

May's presentation will be about leveraging core UNIX services to build a manageable network. NFS, NIS (alias Yellow pages), the automounter, netgroups, and trust can be combined to give a system administrator powerful amounts of control and agility over a network of UNIX servers. This is a compiliation of tips and tricks Dave has used as a system administrator to keep up with a network having a couple hundred UNIX hosts.


Dave Dickerson, is a charter member of the St. Louis UNIX User Group. Dave's background includes: stints as an Software Engineer (SE) for a major UNIX vendor, a System Administrator, a programmer, an Information Technology (IT) Manager, and a systems management consultant. Dave has been working with UNIX and networks for over 17 years.

[ Editor's Notes: Dave's hands never leave his pockets... they don't have to. Dave is Mister Security, he has no real job. They just pay him for what he knows.

Dave's December 1997 presentation for SLUUG was a singularly outstanding one on using free security tools. Just being in the same room with him will make you smarter. ]


The Password File by Mike Kriz


PASSWORDS! Where are they?

  • the /etc/passwd file

  • the shadow password file

  • yellow pages (NIS)

  • Trusted Computing Base (tcb)

  • the /etc/groups file

  • web server passwords

    How are they encrypted?

    How do you access them?

    How do you maintain them?

    This tutorial could almost cover everything you might ever possibly need to know about the password file, it's contents, the passwd command, how to add users, and more.


    Mike Kriz has been an Information Technology (IT) consultant specializing in UNIX and Oracle for over 15 years. He has worked for a variety of clients in the St. Louis market doing Oracle based business applications and data warehousing.

    He has been a SLUUG board member and steering committee member in the past and has been doing tutorials for the Unix Users Group for quite a few years. For some reason not totally clear to him, members have found his tutorials either interesting, informative, useful, or entertaining enough in the past to ask for reruns, so he keeps doing them!

    [ Editor's Notes: Mike's last tutorial for SLUUG was... well, just glowing. This guy does nuclear physics as a hobby. He even glows in the dark! ]

    Special Promotion(s)

    blue triangle right Title of the Month

    The 25% discount special this month is on Managing NFS and NIS and all Nutshell books.

    All regularly priced titles are 10% off retail cost at the general meeting.
    (Excludes featured, or specially priced or promotional items)
    O'Reilly Logo

    The O'Reilly and Associates line of books is available at each monthly general meeting as a convenience to our members.

    Each month features a book related to that month's presentation or tutorial topic.

    Discounts off retail cost are offered to all members and each month's featured book(s) may be additionally discounted. Usually, all titles are discounted 10%, while special titles are discounted 25%.

    Upcoming Meetings

    General Meeting May 12, 1999 at 6:30 PM
    Sunnen Products
    7910 Manchester
    St. Louis, MO

    Steering Committee May 18, 1999 at 6:00 PM
    Daugherty Systems
    One City Place (2nd floor)
    Creve Coeur, MO

    ITEC 99 May 19, 1999

    ITEC 99 May 20, 1999

    Linux SIG May 20, 1999 at 7:00 PM
    ( TOPIC: ) Something Wonderful by Some Guy
    Indian Trails Library
    8400 Delport Drive
    (at Midland)

    Java SIG
  • [Not part of SLUUG]
  • May 20, 1999 at 6:30 PM
    [Overlaps Linux SIG meeting]
    ( TOPIC: ) Java Modeling in Color with UML by Peter Coad
    Edward Jones at I-270 and Manchester

    Meeting Directions

    The STL!/unix/usr/group meets the 2nd Wednesday of every month at Sunnen Products, 7910 Manchester Blvd, just east of Hanley on Manchester.

    Directions From Downtown

    1. Take 40 West to the Hanley exit.
    2. Turn left (south) onto Hanley.
    3. Turn left (east) onto Manchester, then turn right ASAP into the Sunnen Products driveway.

    See map at

    (NOTE: A security guard from Sunnen is scheduled to be at the door from 6:20 PM to 7:20 PM to allow entry. After 7:20, the door will be unattended and attendees may not be able to enter.)

    The SLUUG Steering Committee meets the Tuesday following the general meeting at 6:00 PM in the 2nd floor training room of Daugherty Systems, One City Place in Creve Coeur.

    The SLUUG Linux SIG (SLUUGLS) meets the 3rd Thursday of every month at the Indian Trails Public Library.

    See map at

    Article(s): The following article(s) express(es) personal opinions and SLUUG exerts no more editorial control over such content than does a public library, bookstore, or newsstand. Any opinions, advice, statements, services, offers, or other information or Content expressed herein are those of the respective author(s) and not necessarily supported by SLUUG. SLUUG does not guarantee the accuracy, completeness, or usefulness of any content, nor its merchantability or fitness for any particular purpose. ITEC 99 Is This Month !

    ITEC (Information Technology Expositions and Conferences) Expo 1999:

    America's Center, Downtown St. Louis, May 19-20

    Visit our website at , and go to our ITEC icon link for up to the minute information on show details or contact our booth manager, Christine Wanta, by

    For approximately the past nine (9) years SLUUG has had a presence at the annual St. Louis ITEC Expo. This year's ITEC Expo will be at the America's Center downtown, Wednesday May 19th and Thursday May 20th.

    Free show tickets were distributed at the April 14 SLUUG general meeting and the April 15 Linux SIG meeting. Remaining tickets will be available at the 12 May SLUUG general meeting. Please mark your tickets as coming from SLUUG - the St Louis UNIX User's Group. When you register (or pre-register) indicate the "Association" category and enter "SLUUG"; so that we continue to get more tickets next year.

    We need YOU! Our booth is staffed by membership. If you can come to the show, plan an hour (or more ;-) to work our booth. Even one hour will give someone in the booth a break.

    Each year our participation at ITEC allows us to let a lot of people know of the group's existence. It is amazing how many people have learned that our group is a resource here in town just because they happened to walk up to the booth. (It doesn't hurt to be the one in the booth talking to them. ;-)

    And, as usual, we need those REAL STALWARTS! Each year, there have been a few people who have devoted an entire afternoon, morning, day, or even BOTH days to working our booth, getting it set up, etc. We always need a few more of you to volunteer.

    Also our O'Reilly & Associates books will be sold there. The ITEC show sales volume generated is one of the reasons we continue to be able to offer the ORA books at our meetings.

    We look forward to seeing you there and hope you can help us make this year's ITEC 99 our greatest success to date.

    -- SLUUG Steering Committee

    PerlMongers Source Code submitted by David Barnes

    The source code powering the St. Louis Perl Mongers web site is now publicly available at the group's web site of

    Everyone is invited to both use the scripts and improve upon them. The code is distributed under the same license as Perl (either GNU or artistic).

    To keep track of updates and changes to the Perl scripts, the group is using a CVS version control system. Via a web interface, visitors can: read about changes in the code; download current or historical versions; and run "diff" commands.

    Scripts available include: a form feedback script, a script that allows visitors to submit Perl tips, and of course the web interface to the CVS system.

    If you have any questions, send

    Handy Little Loop from somewhere

    This following trick works with the bourne shell and the bash shell. At the shell command line prompt "username$" type:

    ... username$ while true

    ... { the system will respond with a secondary prompt, such as ">", continue as shown }

    ... > do

    ... > clear { if you want to erase screen }

    ... > date

    ... > vmstat { this is just an example command }

    ... > free { any other command you want to use }

    ... > sleep 5

    ... > done


    ... { use Ctrl+C to cancel the loop }

    Interesting Browsing!

    To keep up with NET events: daily news of mostly (but not only) Linux events. news for nerds - stuff that matters! daily updates of Internet software releases. (check out the "appindex" button). Because There's More Than One Way to Compute. Linux Weekly News. Tracks when numerous WWW pages were last updated.

    To watch your back: The Mother of All Security sites. Another all in one security information and news site. Secure UNIX Programming FAQ guide for programmers (NOT administrators).

    Developers: The Solaris Developer Connection site

    To configure a Linux machine: Specs on over 2100 monitors from 150+ manufacturers. From Monitor FAQ page follow Performance Parameters link. The monitor data base that had the one that I wanted! Knowlege base of Linux compatible modems!

    For the Linux beginner: Useful info and easy downloads. - ...for newbies. - Linux Administration Made Easy" (LAME) Pre-Release - Place to stand up and be counted.

    History: A small collection of free clues Microcomputers - Chronology of Events My favorite historical document on the entire Internet.

    Movie: detailed virtual reality by AIs that take over the world.

    Infrastructure: Current history, FAQs, white papers and case studies. Linux/UNIX Independent Group for Usability Information (Univ of Mich).

    If you are the kind of person that occasionally wanders thru the public library or a book store to see what can spark your interest this is the site to visit. Exploration may not seem worthwhile until you have poked into unfamiliar areas. I added this one to my bookmarks because I know that I want to come back when I can dig deeper and have the time.

    This is the most interesting new site that I have seen in the last two months. It's front page is almost bashful and quite humble; yet, underscores the great work that has begun here. The Resources sections are jewels, not the News section for being the hottest and latest items; but, the Open Source Software (OSS), Linux and Collaboration sections because they focus your mind on the basic research and infrastructure. This site has a lot of potential.

    CTI Added To Our Majordomo Mailing Lists!

    Now available for all SLUUG members, Unix fans, and hangers on--SLUUG mailing lists!

    The following lists are currently available:

  • announce - for SLUUG announcements, newsletters, etc. note: restricted posting, low traffic

  • discuss - for general discussion of SLUUG, Unix, or whatever else may be applicable

  • steercom - SLUUG steering committee discussion

  • CTI - our NEW list - Computer Telephony Integration GPL project

    To join any of these lists, start mail from the address that you want subscribed and with the message body containing only:

    subscribe listname

    ...where listname is one of the above lists. The message subject does not matter.

    In other words one of the following should be in the body of your message:

    subscribe announce

    subscribe discuss

    subscribe steercom

    subscribe cti

    Posting to "announce" will be restricted and have low traffic. The other lists will be restricted to subscribed email addresses, so if you wish to post from multiple email addresses, be sure to subscribe from each of them.

    [Editor's Notes: Posting to the lists is simple; but, not obvious. Once you have subscribed, you would post to "cti" simply by addressing your email to "". For more extensive information, send with the message body containing only:


    I say again: Nothing is really intuitive or obvious with computers or people.]

    Personal Commentary submitted by Gary J. Meyer

    The following PERSONAL COMMENTARY expresses personal opinions and SLUUG exerts no more editorial control over such content than does a public library, bookstore, or newsstand. Any opinions, advice, statements, services, offers, or other information or Content expressed herein are those of the respective author and not necessarily supported by SLUUG. SLUUG does not guarantee the accuracy, completeness, or usefulness of any content, nor its merchantability or fitness for any particular purpose.

    A federal judge in Philidelphia has once again saved our 1st Amendment Freedom of Speech / Press on the Internet.

    The judge issued a restraining order on 19 April, blocking enforcement of COPA (The Child Online Protection Act).

    COPA has also been refered to as CDA 2. CDA, the Communications Decency Act was quickly hidden into the Telecommunications Reform Act the other year. The Supreme Court later declared it clearly unconstitutional. COPA is just another attempt to slip in these abuses again. The concept is to allow the government to declare content on the internet as offensive and intimidate ISPs, BBSs, and others running the net.

    This time COPA was passed in the last days of congress before the November election. There was no public debate. It slipped thru and became law with the advantage of being buried on the back page after the election and impeachment coverage.

    But...."its just to protect children", you say. Why should we question it?

    Two thoughts come to mind. First, aren't children important enuff that you want them protected by parents? I wouldn't trust them to the government.

    Secondly, remember Lord Akton's comment,"Power Corrupts..."?

    "We have to protect the children at all costs! Don't ask questions!". The Nazi's said they needed to protect society from hearing the Communists and Jews. The Soviets said they needed to protect society from hearing the royalists and bourgouis.

    My favorite was William Schaire's (Death of a President) interviews with Mao Tse-tung. Before the Communists siezed the mainland in '49, Mao told Schaire in an interview that there would be "Freedom of Speech". After the Communists were in power for a few years and obviously surpressing dissent, Schaire had the opportunity to intervew Mao again and asked about his promised Freedom of Speech. Mao explained that ....OF COURSE it was obvious that such Freedom didn't applied to Speech Mao found objectionable!

    OF COURSE..."absolute power corrupts absolutly!"

    You may disagree with me; but, wouldn't it have been better to have this debated publicly in the "world's greatest debating hall" rather than "snuck into law at nite"? Defend your rights to the internet...or they may disappear!

    Special Interest Groups (SIGS)

    As our membership grows, we have had some inquiries about the possibility of having Special Interest Groups in several areas. If you are interested in starting or participating in a SIG for System Administration, Networking, C, Object Oriented Programming, a specific vendor, etc., please call Dave Mills at 230-5151, extension 103, or contact any officer of the group.

    St. Louis Unix Users Group - Linux SIG (SLUUGLS)

    Visit the Linux SIG home page ( for the latest meeting details.

    Indian Trails Public Library
    8400 Delport Drive
    (at Midland)
    From 170: Exit Page east to North-South Rd., go left on North-South Rd. to Midland, go left on Midland one block to Delport, the Library is on your left (see map at

    For more information on SLUUGLS refer to the WWW home page for the group at or contact Matthew Feldt by

    Computer Telephony Integration User's Group (SLUUG CiTI)

    The CTI SIG is no longer having regular meetings and is currently using a webboard format.

    The Computer Telephony Integration (CTI) Users Group is a non-profit organization open to developers, end-users, sales people, and others who share the common interest of melding the telecommunications and computing worlds.

    For more information on SLUUG CiTI contact Tony Zafiropoulos by or (314)878-9855.

    Digital Alpha SIG

    The Digital Alpha SIG is for those interested in Digital UNIX and the DEC Alpha architecture. Visit the Digital Alpha SIG's home at for more information.

    St. Louis UNIX Users Group Steering Committee

    The SLUUG Steering Committee meets the Tuesday following the general 2nd Wednesday meeting at 6:00 PM in the 2nd floor training room of Daugherty Systems, One City Place in Creve Coeur. The guard can direct you to the meeting location. Anyone is welcome to attend. If you would like to become more involved in the planning of SLUUG, feel free to join us at the next Steering Committee meeting. Meetings usually last 1.5 to 2 hours.


  • Analysts International
  • Andersen Consulting
  • CIBER, Inc.
  • Cypress Systems, Ltd.
  • Daugherty Systems
  • Informix Corporation
  • Maryville Data Systems, Inc.
  • O'Reilly & Associates
  • Renaissance Worldwide, Inc.
  • Sun Microsystems
  • Sunnen Products
  • Sykes Enterprises, Inc.
  • Venmar Systems, Inc.

  • The Law Offices of Rich McLennan, send

    For more information about sponsoring the St. Louis UNIX Users Group, contact Ed Wehner, send

    SLUUG on the World Wide Web

    The St. Louis UNIX Users Group maintains a WWW page at Visit us to learn more about who we are and what we do, visit other UNIX user groups' WWW pages, sign up for a SIG, or just to browse.

    SLUUG Administration is volunteer based.

    SLUUG is looking for volunteers to help with presentations, web page development, managing corporate sponsorships, and many other tasks. If you would like to help out, contact Chris Wanta by or visit


    We publish other user group meeting schedules on a reciprocal basis. If you are a member of another non-profit group, please inform them of our policy and invite them to exchange meeting information by, or call any of the SLUUG officers.


    Address Changes
    and Membership
    Klaus Mueller Home: +1 (573) 334-6477
    331 S Spring Ave
    Cape Girardeau, MO 63703
    BBS Questions Jim (Knight) Ford
    Corporate Sponsors Ed Wehner
    Editorial team:
    Publisher Sanjiv Bhatia Home: (314)519-9272
    Work: (314)516-6520
    FAX: (314)516-5400
    Editor Stan Reichardt Home: (314)298-1183
    O'Reilly Books Dave Mills Work: (314)230-5151, extension 103
    Presentations Open Position Currently send info/ideas to
    Steering Committee
    Gary Meyer Home: (314)781-8644
    SLUUG Treasurer Christine Wanta
    Special Interest Groups (SIGs)

    Computer Telephony
    Integration (CTI)
    Tony Zafiropoulos Phone: (314)878-9855
    Linux Matthew Feldt Home: (314)429-5433

    Submitting Articles to the SLUUG CRONicle

    If you would like to submit an article to the CRONicle of general interest to the members of the St. Louis UNIX Users Group,send The deadline for article submissions is two weeks before the next main meeting.

    SLUUG PO Box

    The St. Louis UNIX Users Group has a P.O. box. All official correspondence with SLUUG should now be sent to:

        St. Louis UNIX Users Group
        P.O. Box 1184
        Fenton, MO  63026-1184