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October 2004

rebol: Tech Words of the Day 
- Another odd little scripting language. I was particularly amused at the so called "FAQ".
 
Switches damaged by UPS? 
- He heard a longish beep and everything stopped. UPS's protect, but they can also damage equipment.
 
Setting up a new firewall 
- I double checked my work, didn't see anything wrong. Checked it again, power cycled this hardware and the DSL device. Still couldn't ping the gateway.
 
T-1, T-3, OC-3: Tech Words of the Day 
- A T-1 line is 24 telephone channels of 64Kb each. A T-3 is 672 channels or 28 T1's. You'll also see a T-1 referred to as DS1, and T-3's as DS3. A T-1 is about 1.54 Mbps, a T-3 about 43 Mbps. Above that, we get into OC (Optical Carrier) territory.
 
SCO's City to City Tour 
- SCO used to have quarterly regional meetings for resellers and end-users, but they don't come around for dog and pony shows too often any more. They did do one this month, though, and I attended the MA presentation today. Four SCO folk, seven resellers, one end user.
 
reptile: Tech Words of the Day 
- http://reptile.openprivacy.org/. Maybe I just don't get this. Reptile distributes RSS feeds: OK. Wouldn't a supernode be the same as any RSS integrator like Syndic8?
 
fgconsole: Tech Words of the Day 
- This Linux command returns the number of the console you are using: if you were on ALT-F1, it would return 1, ALT-F2 would be 2, etc. It's hard to imagine where this would be useful except perhaps in some script that you don't want to run on certain consoles for some reason.
 
honeyd: Tech Words of the Day 
- A honeypot that uses separate scripts for the services you want to trap. I couldn't make it work on a brand new RedHat system.
 
Linux|Unix Cookbook Second Edition 
- When this book fell out of its shipping envelope, it made quite a thunk as it hit my desk. No wonder: at almost 800 pages, this is quite a chunk of reading material.
 
alien: Tech Words of the Day 
- Convert Debian .deb to RedHat RPM: http://www.kitenet.net/programs/alien/. It's a Perl script. Converting can be just the beginning of chasing down dependencies, so don't expect that this just lets you automatically use Debian packages.
 
Cartoons:Server Down 
- I guess it's funny to me because I actually found something much like this once when the message was 'the server is down'..
 
Understanding Open Source and Free Software Licensing 
- I honestly didn't think I'd find this as interesting as I did. As important as licenses are, an annotated listing of them didn't sound like anything I wanted to flop back on the couch with. However, the author has managed to make this both interesting and educational.
 
Using rsync for machine replication? 
- Yesterday I was at a client site where they explained they wanted to keep a stand-by server up to date and ready to take over in case of main system failure. Fine, lots of people do that, and currently they are doing it by restoring backups every morning. What they were asking about was using rsync or some other mechanism to keep the machines more current.
 
see: Tech Words of the Day 
- A useful Debian tool that lets you "see" compressed files without uncompressing them.
 
pragma: Tech Words of the Day 
- A directive to a compiler or interpreter that tells it something about how it should do its job. It's not part of your program per se, though it may affect the final result.
 
less: Tech Words of the Day 
- As they say, less is more, both in terms of it having the same function and because it really is.
 
Debugging Facetwin Remote Printing Connections  by Dirk Hart
- I got a call today from one of my customers complaining that their remote printer was no longer printing. "What changed?", I asked. "Nothing at all!", she replied in her charming southern drawl, "It just stopped printing!". Well, I suppose some folks would have me believe that gremlins come around in the night and reconfigure their PCs, but I'm not buying it. There's plenty of stuff around here that needs reconfiguring and I don't see any of that happening.
 
SCOoffice Mail Server 
- As this is basically a repackaging of the Bynari product, which does run on Linux, I have to openly wonder why you'd want to run this on SCO unless you were already running a SCO server for some other reason. If that were the case, I'd then question why you are mixing an important application like mail with some other app: mail should really run on a separate server as it normally has much more serious security issues than other internal servers. So, overall, I don't see a bright future for this.
 
cmp: Tech Words of the Day 
- I often forget about 'cmp' and use 'diff' when all I really want to know is if two files are the same: cmp -s file1 file2 || echo 'Not the same'
 
Finally solved FACTS crashing issue 
- BBX Facts config.bbx is a weak point. Terminal definitions are required for every pseudo tty that might be used - there is no default.
 
Mac Opener worm is not a worm. 
- Gaad. Are these people really this dumb?

All over the place I'm seeing reports like the one above warning Mac users that they too are vulnerable to all the awful viruses and worms that plaque Windows users. Naturally, as I am a Mac owner (and Linux and Windows and..), I investigated, and I have to call B.S. on this one.
 
Assigning terminals in BBX config.bbx   by Dirk Hart
- Because pseudo tty numbers are assigned on a first-come first-served basis it can be difficult to assign the users the same 'terminal number' each time they log in . Here is a nifty way to tame those pesky tty numbers and get them to settle down.
 
Rewards, Control and Open Source 
- People have often assumed that there must be some reward mechanism at work: peer recognition, some amount of fame, etc. But this study suggests that the reward can be entirely internal, that doing the job is reward enough.
 
Great Ideas and Religious Fervor in Linux 
- With specific regard to Linux, there is a little bit of the under-dog mentality mixed in here too. When you know in your heart that you are "better", yet the world doesn't see it, criticism can be harder to swallow.
 
strace, trace: Tech Words of the Day 
- System Call Trace, strace on Linux, often just trace on other Unixes. I have used this tool many times to track down baffling application problems. For example, I recently had a client transfer Cobol programs from an old SCO system to Linux.
 
Windows Startup Programs, viruses, updates and spyware 
- Maybe someday dealing with Windows problems won't be part of our lives, but for now, most of us have to deal with these things now and then.
 
shtool: Tech Words of the Day 
- While its primary intent is for use within installation scripts, it can also be useful for general scripting and is very educational with regard to learning portable shell scripting.
 
amavis: Tech Words of the Day 
- Amavis is a glue script that interfaces an MTA like sendmail, qmail, etc. with actual virus scanners. Because mail systems vary so much in their configuration, installing Amavis and whatever scanner you actually will use can be confusing.
 
Cartoons:Inspiring Confidence 
- Inspiring Confidence - don't hum 'If I only had a brain' while working on our computer.
 
Cloning a directory structure without copying files 
- Blog # 1124 Cloning a directory structure without copyingfiles
 
Security Paranoia - restricting ssh access 
- I had email from someone today whose system was hacked, apparently by a dictionary attack over ssh. They overwrote most of his hard drive with "DIE SCO DIE". He said there were "over 8000 root login attempts and another 6000 for various other names".
 
A Nonvolatile Memory Overview  by Jitu J. Makwana, Dr. Dieter K. Schroder*
- This paper presents a basic nonvolatile memory (NVM) overview. Section I begins with the introduction including a brief background of NVM's and the common terms used in the memory industry. The description and explanation of how an NVM is programmed (adding electrons) using hot-carrier injection is covered in section II. Section III covers the erasing or removing of electrons from floating gates of NVM's. A brief mechanism of Fowler-Nordheim tunneling is covered. Section IV introduces the model that can be used to predict the NVM programming characteristics. The hot-carrier injection model addressed is the "Lucky Electron" model. Section V covers the reliability aspects of NVM's. The common reliability issues an NVM encounters are the data retention, endurance, and disturbs.
 
Rebuilding failed Linux software RAID 
- Rebuild crashed Linux raid. Recently I had a hard drive fail. It was part of a Linux software RAID 1 (mirrored drives), so we lost no data, and just needed to replace hardware. However, the raid does requires rebuilding. A hardware array would usually automatically rebuild upon drive replacement, but this needed some help.