http://www.systhread.net Systhread is a Free journal about BSD, Linux, and Unix Hobbyist, Programming and Administration en-us Tue, 20 Sep 2011 21:12:00 EDT http://systhread.net/texts/201109wrapmania.php Ever have to run a program with a variety of options over and over again? If your a Unix, Linux, BSD, Mac etc. programmer and/or sysadmin then... yes you have. The key to success of course is my favorite sysadmin attribute: laziness. In this text a look at one simple wrapper for cron and a Perl library script wrapper. Tue, 21 Jun 2011 20:12:00 EDT http://systhread.net/texts/201106cmod1.php Many programs come with modules that can registered and loaded. Some are on demand, others compiled in while still others are precompiled and can be loaded on demand (several Operating System kernels come to mind that have such a capability). In this text, an example of a program that allows a module to be written and compiled onto a program with relative ease. The example program is the dnet test program which ships with libdnet written by Dug Song. Sat, 26 Mar 2011 18:20:00 EST http://systhread.net/texts/201101autonag.php Ever had to setup nagios monitoring for a group of very similar systems? Say, perhaps, high performance compute nodes? Well, I have. And being a lazy system admin, I decided instead of having to make (N) changes to the config file I would prefer to simply autogenerate the configurations. Ideally, one might use a base configuration file. Of course, even that was too much work for me, I just jammed it into two shell scripts. Regardless, here is a simple method for quickly generating nagios configurations that should scale quite nicely. Sat, 01 Jan 2011 09:07:15 EST http://systhread.net/texts/201101infra.php Can the same methods as Rapid Application Development and Prototyping be applied to infrastructure? Or does infrastructure always have to be engineered? The real answer is of course (as usual per my essays) it depends. Instead of conjecturing when it might work this text will look at three examples. One where it did not work, one where it kind of worked until it went off the rails and one where it worked like a champ. Sat, 01 Jan 2011 09:08:00 EST http://jasonrfink.com/ After several years of procrastination I finally sat down and created a personal website. Okay in reality I was bored on a snowy winter day but either way it did finally get done. I don't think the two or three longtime readers of this site will learn anything new. So if you are bored out of your skull please do feel free to visit my personal site to help burn away what would be otherwise productive milliseconds. Sun, 07 Nov 2010 15:00:00 EST http://systhread.net/texts/201011cs1.php At face value Rob's rule number 5 makes sense. But what is Rob actually saying? In complex software systems it might be difficult to track down and identify how the rule of evolving functions to deal with data worked. So why not use a small microscopic example instead. Taking a small program, a passive network scanner, from data structures to operations on the data structures illustrates Rob's rule number 5 perfectly. This is an interesting experience from my perspective as most of the programs and scripts I have written deal with transitionary data. What I mean by transitionary is simply find it, operate on it and/or print it then move on. Not an unusual trait in system administration centric programs. While working on a passive scanner that could also verify a port I witnessed rule number 5 occur right before by fingertips. Fri, 24 Sep 2010 21:00:00 EST http://systhread.net/texts/201009snortparse.php The Snort Intrusion Detection System or IDS is great. Snort can detect all sorts of interesting traffic. I had to write a script to parse the snort alert log and mail me only stuff I was interested in. The other rule was I needed to keep it as simple as possible. Sat, 04 Sep 2010 21:00:00 EST http://systhread.net/news.php#netrecon178 Netrecon now is a single small utility which calls programs via function pointers. The programs are an active scanner, active ipv6 single port single host scanner, a pcap powered passive scanner, a mini tcpdump utility and an arp sniffer. There is still a lot in the TODOs such as validating passively detected ports, expanding the pcap utilities and adding better ipv6 support.