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Reiser4 Filesystem

At one time, Reiser was poised to replace ext2, but most vendors turned to ext3 instead. Some of that may have had to do with the murder conviction of Hans Reiser, though some folks still do argue its technical merits.

Title Last Comment
I have a best selling book on Amazon!  
- To my great surprise, I have a best selling book on Amazon! -

Why doesn't rcp work for root?  
- Why doesn't rcp work for root? I get Permission Denied even though it works with other users? -

How can I prevent logins?  
- I need a way to disable logins from the root user account without being at the server console itself -

Where can I get a hexadecimal or binary calculator?  
- Where can I get a hexadecimal or binary calculator that will help me manage hex and binary numbers? -

Unix and Linux startup scripts Part 4, Systemd  
- Systemd is gaining favor in Linux distributions. This is a big change from inittab and everything else -

Ubuntu service start bug  
- Ubuntu service start bug prevents restart of squid3 -

Restrict script to console use  
- How to restrict a shell script to prevent use by ssh or to only be used at the console. -

The truth about Linux   2014/04/08 SachinGopal
- I have been lying to you. You should NEVER use Linux for anything! Pay attention as I explain why. -

The Seven Layer inedible OSI cake  
- 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   2014/04/07 Keith
- Like Rodney Dangerfield, SysAdmins don't always get the respect they deserve. -

Trapping errors in Bash  
- While I think you need to avoid getting too clever in shell scripts, trapping errors can be useful. -

'ps' and 'grep'  
- 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  
- 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   2013/09/10 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?   2013/08/07 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  
- 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  
- 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  
- 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. -

Printing multiple files  
- 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? -

LOD Communications, Inc.
When bad things happen to good computers   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?  
- 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?   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?  
- 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?  
- 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   2013/07/30 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  
- 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  
- 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  
- Crashes, panics and freezes: all work halts and you can't help being surprised. What just happened? -

Passing shell environment variables  
- Is there anyway for a child process to set an environment variable visible to its parent? -

Deleting a lost file name - delete unremoveable files  
- 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  
- 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?   2013/11/13 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  
- 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  
- I kept forgetting to send our club meeting notices to the newsletter. Google Calendar couldn't help me, so I wrote this script. -

Here files (shell scripting)   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   2012/10/25 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   2012/10/07 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. -

Simple outgoing email for SCO Unix (and Linux)   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   2011/11/23 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. -

Ucertify Review   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   2011/09/10 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  
- 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  
- 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   2011/08/16 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   2011/08/14 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?   2011/08/20 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  
- 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. -

Moved to Linode.com   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  
- Keeping an old SCO system running is sometimes necessary. If that's what you find yourself facing, here aere some things you need to know. -

Linux colors ls ––color command  
- 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?   2011/06/02 KenPorter
- Although fsck hasn't needed scratch files for a while, large disks are reopening that need. -

Finding Yesterday's Date   2014/02/05 TonyLawrence
- How to find yesterday's date on Linux, Mac and any other Unix. -

Yesterday's Date   2010/04/01 TonyLawrence
- Recently I was asked how to write a script that would automate the task of copying a log file to another directory -

Murder and mayhem - killing users processes   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   2015/04/14 TonyLawrence
- 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   2011/04/05 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   2011/04/02 TonyLawrence
- A detailed history of a SCO to Linux Conversion - including desktop users. -

Smarter HTML Link Extractor   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?  
- 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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