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Title Date Comments
Restrict script to console use   2013 11 
- How to restrict a shell script to prevent use by ssh or to only be used at the console. -
The truth about Linux   2013 08  2014/04/08 SachinGopal
- I have been lying to you. You should NEVER use Linux for anything! Pay attention as I explain. -
The Seven Layer inedible OSI cake   2013 08 
- The other day I had to explain the OSI model to a customer. I'm not usually this cruel, but (as they say) he asked for it. -
Let's be serious about System Administration   2013 08  2014/04/07 Keith
- Like Rodney Dangerfield, SysAdmins don't always get the respect they deserve. -
Trapping errors in Bash   2013 08 
- While I think you need to avoid getting too clever in shell scripts, trapping errors can be useful. -
'ps' and 'grep'   2013 08 
- Grepping lines out of ps is a common task. Unfortunately, it's also easy to go terribly wrong and not get what you expected at all. -
tput and stty   2013 08 
- tput and stty are related in the sense that they both have to do with how a Unix terminal behaves. Tput is perhaps less important than it used to be, but still useful -
All about ping   2013 08  2013/09/10 TonyLawrence
- Ping is a useful network diagnostic, but it can have its own issues - timeouts, duplicate packets, intermittent issues and more. -
Is rm final? Can I get my files back?   2013 08  2013/08/07 BigDumbDinosaur
- Is rm final? Are the files gone forever? It depends on what you mean by really gone and also depends upon your file system, your OS, and rm itself. -
Run a script every other day but not on weekends   2013 08 
- While this became much easier with Vixie cron, there are still circumstances that need some extra help in the script. -
Length of a domain name   2013 08 
- What IS the longest possible domain name and why isn't it in the book of Guinness World Records? While we're at it, what is a domain name anyway? -
Sparse Files   2013 08 
- Sparse files are a result of the way systems allocate storage space. Sparse files appear to take up much more disk space than they actually do. -
 
 
Samepage - Redefining how people create and share information
 
 
Printing multiple files   2013 08 
- I have 25 .txt files that I would like to print. They are named 1.txt, 2.txt and so on. How can I do this? -
When bad things happen to good computers   2013 07  2013/07/31 TonyLawrence
- Computers are usually very reliable, sometimes running for decades with no attention. On the other hand, sometimes bad things happen.. -
What does 'everything is a file' really mean?   2013 07 
- Everything is a file? How ridiculous: is a horse a file? How about a pitcher of beer dumped over the nearest Unix geek's head - is THAT a file? -
Why won't IT staff recommend Macs or Linux?   2013 07  2010/01/20 anonymous
- Microsoft pays close attention to what people want. They may do a horrible, botched job of providing it initially, and at the next revision, and so on, but eventually they do provide decent products. -
Why does so much of Unix and Linux have to be hard?   2013 07 
- Obviously you have REASONS for sharing whatever it is you shared. Sometimes those reasons are completely altruistic, sometimes not. -
Shebang - What's the point of #!/bin/bash?   2013 07 
- Shebang, hashbang, pling - whatever you call it, what's the point? What does it do? Do you need it in shell scripts or not? -
Wall and write   2013 07  2013/07/30 TonyLawrence
- The Unix/Linux "wall" command does that. Login as root, type "wall" <ENTER>, then whatever you want to say (multiple lines are OK), follwed by <ENTER> and then CTRL-D -
Difference between /dev/sr0 and /dev/scd0   2013 07 
- Why does the system call the same device by two different names: There isn't necessarily any difference at all. -
Determine Unix/Linux version and cpu's   2013 07 
- Usually some variant of uname, often 'uname -a', but all sorts of other possibilies; it depends on the Unix and in some cases even the specific version. -
Mysterious panics and freezes   2013 07 
- Crashes, panics and freezes: all work halts and you can't help being surprised. What just happened? -
Passing shell environment variables   2013 07 
- Is there anyway for a child process to set an environment variable visible to its parent? -
Deleting a lost file name - delete unremoveable files   2013 07 
- It HAS a file name- it probably has control characters in it that are confusing the display. Try ls -b. If that doesn't work, do "ls -l > /tmp/t" and the "vi /tmp/t" -
View large files without more or less   2013 07 
- I have a rescue disk that doesn't include "more" or "less" - how can I examine large files? -
How do I find out what IP address a user logged in from?   2013 07  2013/11/13 TonyLawrence
- Obtaining a client IP address on Linux/Unix is not always direct or easy. You may have to dig it out of shell command output. -
Using SCO Unix as a firewall   2013 07 
- Given the current cost of hardware and the availability of Linux software, why on earth would you want to run a firewall on a production server? -
Early reminders for first Monday of month events   2012 10 
- I kept forgetting to send our club meeting notices to the newsletter. Google Calendar couldn't help me, so I wrote this script. -
VMware Fusion vs. Parallels Desktop   2012 10  2012/10/17 BruceGarlock
- Similarly priced, and VMware does have the advantage in premade machines, but I like Parallels better. -
Here files (shell scripting)   2012 10  2012/10/09 TonyLawrence
- Once again, I've been bitten by not having read the manual recently. This bite really annoyed me. -
Upgrading to Ubuntu 12.04 LTS Server   2012 10  2012/10/25 TonyLawrence
- My upgrade from 10.04 LTS to 12.04 LTS went faster than I expected, but there were surprises at the end. -
No clobber scp - scp without overwriting   2012 10  2012/10/07 TonyLawrence
- Although you usually want scp to update files, there are times when you definitely do not. I wrote this script to avoid overwriting existing files. -
Using Kerio's Linux Versions   2012 10 
- Kerio offers Linux versions of all their products, either as virtual machines or Linux packages. Many Windows users avoid these, but should not. -
Kerio Connect Mail Server Configuration Guide   2012 09 
- Important things to know about Kerio Connect Mail Server configuration. Don't miss these settings and features! -
Kerio Troubleshooting   2012 05  2014/07/03 TonyLawrence
- There are only a very few things that will completely prevent Kerio Mailserver from starting. Usually this would come from a confused or mangled configuration file, but there are other conditions that can cause Kerio to refuse to start. -
Simple outgoing email for SCO Unix (and Linux)   2012 02  2013/05/22 rblake
- Configuring MMDF or Sendmail on SCO Unix was never fun and it only gets worse as fewer people care about any of it. Here is a simple fix for scripted outgoing email -
SATA RDX backup cartridge report for BackupEDGE   2011 11  2011/11/23 BillMohrhardt
- I have been testing an internal SATA RDX drive, made by Quantum, in an IBM x-series 226 server with dual 3.0 Ghz CPU's, 3 GB of RAM, and dual 73 GB SCSI drives configured as a simple RAID 1. The Operating System is Red Hat Enterprise Linux 5.3, Microlite BackupEDGE version 03.00.03 with the RDX cartridge configured as a file system partition. I modified the retention time to be only 3 days, as I was backing up to the same cartridge, and wanted to verify that the program would automatically delete the oldest archive to make room. When we have a cartridge for each workday, I will extend that back out to 2 weeks. -
Kerio Connect Mailserver version 7.3   2011 11 
- Kerio Connect Mailserver version 7.3 is scheduled for release in early November 2011 and adds important features, including a few that I suggested and lobbied for earlier. -
Ucertify Review   2011 09  2014/02/12 BrookA
- Whether certifications have any value is an entirely different question. I would suggest that you NOT bother with certification unless you are planning to apply for a specific job that requires it or if you are just starting out and have no experience to brag about. Many people like myself look upon certifications as having little real value - it's 'book knowledge' that doesn't necessarily translate into real skills. However, some employment opportunities may require these as an indication that you have at least basic knowledge. So let's just leave that argument for another day. The rest of this article assumes that certification has value for you. -
Death of the command line revisited   2011 09  2011/09/10 TonyLawrence
- Five years ago I wrote a little blurb called Death of the command line. As it happened, that article was misunderstood by many who read it - I don't know if it was my fault or theirs, but somehow many readers ended up thinking I was either predicting the demise of CLI's (Command Line Interfaces) or hoping for that demise or both. Nothing could have been farther from the truth. I remain a big fan of CLI's and use them daily. And yet, just five years later and still at risk of angering yet another batch of folk who won't read carefully, I'm going to suggest that predicting the death of the CLI may not be such a bad bet after all. -
Basic Home Networking, Part 3, File and Printer Sharing   2011 08 
- The point of a computer network is sharing. You might not be sharing much, perhaps even only the Internet connection. If that's the end of it, you don't need much more than part one of this series, which deals with the setup of a basic small network. -
Basic Home Networking - Part 2, wireless setup   2011 08 
- Often all that needs to be done is to tell your computer that you want to connect to a wireless network. It's not always that easy, but it certainly can be. However, even if it is that easy for you, you might still want to read the rest of this in case you have problems later. You also might want to read it because being "too easy" to get connected could mean that you are running some security risk and need to address that issue. -
Basic Home Networking - routers and switches   2011 08  2011/08/16 BigDumbDinosaur
- Setting up a small office or home network used to be a fairly complicated task. Aside from the technical knowledge needed, there was expensive equipment to buy and specialized tools for wiring. That's all changed - the necessary equipment is cheap and readily available and it's all very easy to configu re. -
A non-technical guide to understanding and fixing TCP/IP problems on a network   2011 08  2011/08/14 BigDumbDinosaur
- The title is a bit incorrect in the .non-technical. claim, because we are dealing with a geekish subject here and I can't avoid being a little "techie". -
Is Linux becoming insignificant?   2011 08  2011/08/20 TonyLawrence
- How many Linux items have I read? Well, my Linux readers won't like this, because it's just 28. -
Joe's computer turns 3   2011 07 
- I'm really excited because soon I may get to run Linux! I have been hoping for that for years and had just about given up on the idea when they tried to install Windows 7 on my drive. -
Using fail2ban with Kerio Connect mailserver   2011 06  2014/01/05 TonyLawrence
- Fail2ban is fussy about dates in log files; Kerio's security log does not meet its standards -
Moved to Linode.com   2011 06  2011/06/20 Ralph
- I was very unhappy with my former hosting site. Recently I discovered Linode.com and have transferred this site to their XNE VPS servers. -
He needs a SCO box   2011 06 
- Keeping an old SCO system running is sometimes necessary. Here is some help -
TinyTERM ITX for Mac   2011 05 
- TinyTERM ITX for Mac OS X is somewhat disappointing - the emulation is fine, but it is a poor Mac app. -
 
 
Kerio Connect Mailserver
 
 
Linux colors ls ––color command   2011 05 
- Change default dircolors. Personally, I don't like colors in my shell. I think it would be fine as an option, but to have it as the default offends me and many other old Unix hands. -
Why does fsck need a scratch file?   2011 04  2011/06/02 KenPorter
- Although fsck hasn't needed scratch files for a while, large disks are reopening that need. -
Finding Yesterday's Date   2011 04  2014/02/05 TonyLawrence
- How to find yesterday's date on Linux, Mac and any other Unix. -
Murder and mayhem - killing users processes   2011 04  2011/10/28 BigDumbDinosaur
- how to kill all of a specific user's user processes without "killall" - or select a subset to kill -
Converting SCO to Linux - Another one down, two left   2011 04  2013/10/11 BigDumbDinosaur
- Our efforts to get clients off OSR5 and on to Linux commenced in earnest in 2004, which was right after SCO started with their "Linux stole our code" lawsuits. -
Slightly Scrambled - unsorting a file   2011 04  2011/04/05 TonyLawrence
- Here is a typical way to approach the problem. It uses Perl's associative arrays and (somewhat ironically) uses -
A SCO Openserver to Red Hat Linux Conversion   2011 04  2011/04/02 TonyLawrence
- A detailed history of a SCO to Linux Conversion - including desktop users. -
Smarter HTML Link Extractor   2011 03  2011/07/20 TonyLawrence
- Checking links is not really hard; you can actually do it with just a few lines of Perl. -
Environment variables - maximum size of a variable?   2011 03 
- An 18 MB or larger variable is much more than any shell script is likely to need, but it shows that you need not fear assigning large chunks of data -


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