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firstname.lastname@example.org ("...!uunet! rdpub!saletter").
First of all, let me thank you for what looks to be
useful magazine. One suggestion I would like to make
is that you make
your listings available in electronic form. Being able
to submit this
letter via E-mail is very convenient for me. It would
be even more
convenient if I didn't have to type in the listing for
or shell script I found interesting. The ideal situation
for all of the files contained in an issue to be available
ftp. Failing that, an automated mail server, or even
a BBS system,
On to content. I particularly liked the article by Leor
the overnight job spooler. I do have a few comments.
Mr. Zolman is concerned that jobs submitted after the
begun processing for the night will be "lost"
until the next
night. He has added several checks to help prevent this.
there is a much simpler solution. The main body of "onitego.sh"
consists of a while loop wrapped around an if. If the
were added, just before the "fi", then the
priority loop would
reset to 1 on the next iteration, and any newly queued
be caught. The while loop would only terminate after
levels had been found to be empty. The potential hole
for a "lost"
job still exists, but it is VERY tiny.
My other comment is more serious. These scripts, as
they stand, represent
a huge security risk! Since the jobs are run with root
prevents a user from accessing (or destroying!) sensitive
issue needs to be addressed before these scripts can
be used on any
system where the sysadmin has anything less than absolute
the integrity of all users. I've tossed several ideas
around in my
head, but I haven't come up with a secure solution yet.
It has been our intention all along to make SysAdmin
listings available electronically; however, as the Premiere
went to press, we had still not completely ironed out
SysAdmin code, as well as the code for our sister publications
The C Users Journal and Windows/DOS Developer's Journal,
is now available via UUNET for ftp or uucp transfer
(with or without
a UUNET account). See the announcement on page 24 of
this issue for
the gory details.
Thank you for your kind comments about SysAdmin and
the Overnight Spooler article. Your point relating to
issue is right on target; I've tried to at least scratch
of this problem with some comments in my article this
month. The bottom
line, though, is that the Onite system as presented
last issue is
not secure, nor can it be made truly secure without
a total rewrite.
Think of it more as a jumping-off point or initial sketch
Now regarding my way of dealing with late queuing of
jobs: If the technique you suggest for processing "stragglers"
were implemented, then there would be the serious possibility
jobs running in the wrong order. For example, the backup
run before a "late-spooled" job that alters
potentially leading to some confusion if there were
ever any need
to restore from the backup. By explicitly closing the
door at the
time the overnight spooler kicks into action, the potential
problem is eliminated.
Around our office, there's rarely anyone spooling jobs
6 P.M. anyway. If you want folks in your work environment
to be able to spool jobs at any time, and you're not
about the priority issues, then I'd say go ahead and
apply your patch
with my blessings... --lz
Dear SysAdm staff,
Liked your first issue. Some of it was pretty deep for
staff (including me). We develop applications for our
missions offices running DOS and SCO Unix using the
language (similar to DEC's DIBOL).
Really liked the short programs and include our version
and another variation called "newest":
# gives a directory listing
# in reverse size order
ls -l $* | sort -r -n +4 -5 |
pg -sp "<return> = advance
a page, <->
= back up a page, <q> = quit: "
# gives the end of a
# directory listing in date
ls -lrt $* | tail -22 ; date
Is there ANY way for an extension sorted list? I would
kill for this
option in Unix after working on DEC opsys for years.
Future editions could address safe ways to clean up
without using a utility, only tape restore. What does
do to help in this regard if anything?
Managing an elm system could be a big help for us. Just
the elmrc file could be a topic for an issue. I would
like a step-by-step
procedure to take a distributed SCO Unix system and
attach a T-bit
modem and start exchanging files on internet.
Also need to know how to config a system to dial into
another to do
interactive updates for support purposes.
How about an article on system manager suggestions for
and monthly housekeeping? Which are the files that "grow"
and need pruning?
How to use "sa" to tune a system and keep
it simple --
most of us can't spend weeks on this but need a rough
cut to optimize
the significant parameters and not hassle with the final
that takes 90 percent of the effort.
You have a great shot at a great mag, don't blow it!
Operation Mobilization, Inc. - USA
285 Lynnwood Ave., PO Box 444
Tyrone, GA 30290-0444
AT&T: (404) 631-0508
FAX: (404) 631-0439
Thanks for the encouragement (I think). I think you
in luck on most of your suggested topics. For example,
we have installed
and configured (and patched for our idiosyncracies)
elm; we communicate
via a telebit modem and we run SCO (presently Xenix,
but UNIX in the
not too distant future). Thus, we won't even need to
search for an
author to satisfy many of your requests.
All the same, I'd be happy to see manuscripts from others
on any of these topics. System performance tuning is
dark black hole to me. I'd welcome some information
from someone experienced
Meanwhile, here's an answer from Kenji Hino, of SysAdmin's
technical staff, to your request for an extension-sorted
$ ls | sort -t"." +1 -2
I don't know how it happens, but you seem to be able
to publish what
I need within minutes of when I think of it. Miraculous.
Specifically, I'm talking about the overnite scheduler
It seems that I can always count on your articles to
and understandable functions. This is certainly not
your contemporaries! Keep up the good work, please!
I'm enclosing a small program that may repay you in
small way. I needed (wanted) a way to emulate a "hot
in a shell script -- that is, ask a user for a single
entry and act on that keystroke without having to wait
on a carriage
return as is required by the shell's read command. After
different ideas, I contacted an acquaintance at the
Center here on the base. He supplied the following small
Thanks to Lt Caley (AFMPC, Randolph AFB, TX):
Compile: cc -g getone.c -l curses -o getone
newterm(NULL, stdin, stdin);
key = toupper(getch());
the only caveat is that the program will not allow a
ctrl-d to be processed as a shell exit. You must explicitly
provide an exit choice in your script. I hope this is
of some use.
P. David Sorgen
Randolph AFB, TX 78150-6421
DSN 487-3214 Com: 512-652-3214
I run a network of about 700 machines, of which 500
are UNIX (all
kinds of UNIX), and would like a couple of topics discussed.
I am looking for things that are not in UNIX books --
between different vendors. I am hoping that SysAdmin
for serious system administrators.
Topics I'm interested in include:
1) How to put together a "Getting Started with
UNIX, the X-Window
System, etc." packet. I know that most things are
but there should be some general info. I have been an
adm for so long
that I don't remember being a novice user ... and all
the novice users
I have met do not know the questions to ask. (But this
may not be
appropriate for SysAdmin.)
2) How to configure routers and bridges -- not what
is in the books,
but how to block and maybe make firewalls and security
or not every remote network bridge/router should have
a modem, just
3) A script that duplicates a directory from one machine
machine (I would like to know all the ways this could
be done). What
I really want is a standard way of copying a directory
that will keep
everything the same (modifications, times, permissions).
I have run into are with tar and cpio and have to do
length (either 128 or 256 characters absolute pathname
have yet to find a way that works for all cases.
4) Managing files on UNIX boxes. Example: I use symbolic
printcap, networks, sendmail.cf and /usr/spool/mail
or /usr/mail and
for the same types of systems these are linked to one
a backup machine ready). I was thinking of using SCCS
on these files
so I could keep revisions. You could also discuss making
files like mine!
5) Adding new NIS maps like a global telephone phone
list and making
it work with Sun, DEC, Silicon Graphics, Nighthawk,
HP, IBM ... etc
(though most of this is probably available in books).
6) Inconsistencies between all platforms -- like maybe
on /etc/fstab differences on different systems; or NIS
on all systems;
or how Sun will not use bind unless a Sun is the NIS
7) An ongoing list of system administration books that
are good references:
the best books for tcp/ip; the best for NIS and NFS
8) Fast ways of loading different systems (and loading
with as few commands as possible). I have Apollo systems
and can load
4-5 at a time with one command, then reboot and issue
for each. It's an Ethernet load and loading 4-5 machines
puts a local
Ethernet to 25-30 percent and takes 2-3 hours. I am
starting to work
on loading DEC (Ultrix) systems quickly and will probably
use dd in
a script through the SCSI because MOP (from DEC) is
not ready for
serious loading "out of the box." Doing it
by hand is fine
if you have a few days to spend on it and only 10 or
so systems to
load but when you have several hundred and you reload
2-6 of one type
of system a month, this isn't an option.
9) System performance and analysis scripts and tools.
10) Perhaps an issue a year devoted to backups -- the
Some notes and questions:
Are you going to put your code on uunet.uu.net?
Will you try to get real input from USENET?
Are you going to be a mag for real sysadms?
It's time for a serious magazine that takes sysadm out
of the normal
10-30 systems and puts it in with the 300-10000 node
it technical (please!!!) and geared for large networks
with few administrators
(like most large networks), where time is essential
go unread because it takes too long to read through
the stuff that
you already know or that is in all the books in your
office. I thought
your first cut was pretty fair, but "My Favorite
One Liners: Some
Useful Shell Programs" should have just been RTRM
and some tips
on manuals to read (it has no place in a sysadm mag).
If this mag is going to be for sysadms then realize
your readers are
SYSADMS! and they know all about shell scripts and they
know how to
port programs. Please in your articles talk about real
See above (and page 24) for information about network
of the code.
As to whether we'll be for "real sysadms":
I want it to be a magazine for "real sysadms."
You and our
other readers will judge whether we succeed.
I feel strongly that sophisticated practicing professionals
(as opposed to researchers) are seriously underserved
in almost every
technical area. Sophisticated professionals are by definition
a small audience. Most financially viable publishers
in small audiences; they need large audiences to attract
Thus when large publishers bring out so-called "technical"
magazines, they tend to deal in abstract generalities,
in market and
product information, and in religious exhortations.
sophisticated professionals seldom learn much from reading
abstract overview of "How to choose an operating
most likely know where to obtain more specific, reliable,
product information than our small company can generally
and have probably already developed a highly productive
of what is "good practice" -- and thus aren't
for a new religious experience. Moreover, the very practices
make a magazine more valuable to broad, inexpert audiences
eliminating jargon, avoiding platform specific details,
on well-known subjects, "friendlier" restatements
manuals) make it significantly less valuable to the
professional. You can't serve both audiences well in
the same publication.
We do things differently. As of this publication date,
magazine has about 5,000 subscribers. Most of the small
publishers I know maintain that a publication can't
until it reaches at least 15,000 subscribers. Perhaps
they are right
-- by their definition of profitable. But they are also
As we've proven with The C Users Journal and Windows/DOS
Developer's Journal, small, tightly-focused, demanding
can be financially viable. They won't make anyone rich,
but they can
pay their own way.
So, the short form answer to your question is: I have
interest in attracting and tutoring the masses. I want
to be read, respected, and valued by some of the most
experienced System Administrators out there.
Having said that, I must also point out that there are
and experienced people working in systems with 30 users,
there are talented and sophisticated people who aren't
experienced sysadms. And there are experienced and sophisticated
who aren't yet expert in every speciality or platform.
Thus, I don't
intend to publish pabulum, but that doesn't mean every
in every issue will cover something new to you. What
mean is that at least one article in every issue will
bring you something valuable and useful. That's the
best we can hope
to do for any real-world audience -- and it's far better
other UNIX magazine is presently doing for sophisticated
Just received your first issue. GREAT! Insightful,
info SysAdmin types can "real"ly use, right-to-the-point,
congrats on a top notch publication.
Thanks and Bless you. It's great to know we're making