New Messages
Dear Sir, Given that the most recent version is usually the version I want to use, I need to have a dated catalogue of the directory in question sorted in chronological order with the most recent first. The enclosed listing (Listing 1) (E-Media Production Manager's note: Listings found within the New Messages/Letters can be found by scrolling to the bottom of the current page.) shows my solution to this dilemma. If you feel it can help someone else in the same predicament, please feel free to publish it in the New Messages section of Sys Admin.
Yours truly,
To: Sys Admin I appreciate articles like Mr. Berry's. Not only does it provide useful information, it was also short and nontaxing to read. The script he provided also met these criteria. And in the interest of not violating Mr. Berry's short and nontaxing article, here is a small script (Listing 2) (E-Media Production Manager's note: Listings referenced within the New Messages/Letters can be found by scrolling to the bottom of the current page.) that uses the netstat command, which did not appear in his script. His article suggested that high output error rates on your system might "indicate a problem with your own network interface." Furthermore, a percentage of five or greater is offered as a peak or cutoff point between acceptable and unacceptable levels. However, the norm for your system might be different. I have a Sun Sparc Station II with SUNOS 4.1.3_U1. My percentages, thus far, have fallen between 2.52 and 2.8. I obtained those percentages with the attached script. This script sets up a few variables, a function (CALCULATE) and uses bc to do the math. I set the scale for bc to 5. That might be a bit of an overkill, but it can be changed to fit your needs. The CALCULATE function divides collisions (CO) by the output packets (OP) then multiplies by 100 as instructed in the article. I cron'ed the script to periodically mail me the results so I could establish a history. Should a mail message arrive with a percentage that is not normal I can then start researching the problem. Output may also be appended to a file if the need exists.
George Sullivan
From: Alex Newman <sug.org!troll@uunet.uu.net> We had so much fun last year we're going to do it again!
CALL FOR PAPERS Theme:
UNIX and the Law
We are particularly interested in the following topics, but welcome any contribution relevant to the symposium's subject matter: System security; Software law for businessmen; Copyrights vs Copylefts; Encryption systems; Public and private keys; Clipper chips; Digital signatures; Designing software for export; Carjacking on the Information Superhighway. Contributions are also solicited for mini-tutorials, Q&A, system administration, system security, and technical product information. Abstracts are due by 28 July 1995; notification to authors will occur by 18 August 1995; final papers will be due 8 September 1995. For more information, contact:
Sun User Group
To: saletter@rdpub.com Would you tell me where I can obtain public domain source code for NFS and TCP/IP? If you have compiled programs that run on dos/windows, I would like to try them on my AT-class machine and test for SCO UNIX NFS and TCP/IP.
Victor Wu I'm afraid I don't know any complete, public-domain DOS implementation. There are pieces (mostly packet drivers for certain ethernet cards) in various places. In particular, one of the Walnut Creek CD-ROMs (I think it's the CICA Source CD, perhaps they could tell you) has packet drivers. We've been using various commercial implementations. Unfortunately, I can't testify to the usability of that code, since I've never installed it. I'm not even convinced the documentation that comes with it is adequate to manage an installation. I have, however, installed the yggdrasil linux distribution and can highly recommend it. It comes with complete source code for the entire operating system, as well as all the source for all the networking layers. I've also experimented with the slackware and another distribution of Linux. Of the three, I prefer yggdrasil for ease of installation. It's also available from Walnut Creek. I've never tried to adapt any of the Linux code to SCO, so I can't comment on how hard that will be, but I highly recommend it as a platform. We have SCO for our main platform, but are planning to use Linux for several departmental servers.
You can reach Walnut Creek at: --rlw
Mr. Robert Ward I have seen a notable change in your magazine from the earlier Root to Sys Admin. Keep up the good work. Recently I was reviewing my current SCO Xenix system which includes 15 terminals and uses WordPerfect, Informix and Professional software. To my surprise the root system was filling up at a rapid rate. After searching for the cause I found a huge file (over 75 meg) in the directory /etc called wtmp. The file script find /-size +lO00 -print did not locate this file. After calling various people to try to find out more about this file and finally reading the book by Bruce Hunter on Unix administration, I found out that this file stores accounting or system information and builds every minute the system is active. I reduced the file to zero size and my problem was solved. I now watch this file daily. Thought this information might be useful to other SCO Xenix users.
Sincerely,
Listing 1: Lawrence Manns' chronological directory listing
#!/bin/sh # Program : dated.list # Author : L.G. Manns # Purpose : Provide a listing of files in a directory in # chronological order ... most recent first. # # Note : The figure 256 can be modified if one wishes # to view fewer or more than 256. echo "Please enter directory to be listed. \n" read dirname echo "" ls -lt $dirname >/users/tmp.list head -256 /users/tmp.list|more rm /users/tmp.list #end
Listing 2: George Sullivan's collision percentage calculator
#!/bin/sh
############################### GENERAL INFO #######################
#
#Title: NC: meaning Node Collisions, Nasty Collisions
# Number Collisions - your choice.
#Author: George Sullivan
#Date: Wednesday, December 7, 1994
#Description: NC calculates a percentage based on the number of output
# packets and collisions resulting from the netstat command.
# The number of collisions are divided by the number of output
# packets. Then this result is multiplied by 100 to establish the
# the percentage. The percentage can be monitored periodically
# and corrective action can be taken should the percentage be
# abnormal.
#Requirements: NC requires the following unix commands: netstat, grep,
# awk, bc
#####################################################################
############################### VARIABLES ###########################
#HN=Hostname
#OP=Output Packets
#CO=Collisions
HN='hostname'
OP='netstat -ni | grep 'leO' | awk '{print $7}"
CO='netstat -ni | grep 'leO' | awk '{print $9}"
####################################################################
############################## FUNCTION ############################
CALCULATE ()
{
DECIMAL='echo "scale=5 ; $CO/$OP" | bc'
BASE='echo "scale=5 ; $DECIMAL*100" | bc'
echo The collision rate for host $HN is:
echo
echo "$BASE"%
}
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