By: ab

January 9, 2015 11:36 am

LJDT: DOSBox and Game Emulation for Fun

The majority of this series has been very practical, because most of the time I am a dreadful bore and focus on things that are very practical. Want to predictably modify a config file on ten thousand boxes without leaving your computer or manually wasting weeks of your life? Done. Want to read multi-GB files […]

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By: ab

October 30, 2013 10:09 am

LJDT: KVM, Snapshots, and Disk Resizing

Have you ever wanted to resize a disk in a VM and wondered how insanely painful that would be? After all, from the old days of platter-based spinning drives in computers (sorry to those of you still living in those days), before SANs with resizable LUNs, file-backed VMs, and other marvels of recent times, disks didn’t magically resize themselves unless it was to get smaller because they were breaking/broken. As a result, OS’s have learned to handle bad sectors by avoiding them, but growing the current, running disk just seems eerie to me every time I want to do it. Apparently I’m old.

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By: ab

August 7, 2013 2:53 pm

LJDT: LDAP Data and Schema Comparisons

Have you ever wanted to compare data between eDirectory trees, or schema between servers, or objects between entirely different directories (OpenLDAP and eDirectory, for example)? It should be possible, of course, as both systems are accessible via LDAP. Still, how does one go about doing this kind of comparison? Well, because you are running on the right server or workstation, Linux Just Does That.

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By: ab

July 18, 2013 11:26 am

LJDT: Reliable Service / Connection Tests; netcat, not ping, is the correct tool

Me: “I cannot get to your site.” Helpdesk: “Hmm, let me check. I can ping it, so it must be okay.” Me: “No, pinging has nothing to do with access to the site.” Helpdesk: “No, you’re crazy, I can ping it so it’s your problem. Goodbye.” If you have never had this type of exchange with others, you’re lucky. The fact of the matter is that ‘ping’, while a good (but not 100% even here) tool to determine if traffic can go from one IP to another, is a lousy tool for determining if anything more than layer three is working …

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By: ab

January 7, 2010 3:04 pm

Virtualization: What is required for life, the universe, and everything?

When a company considers virtualizing some part of its infrastructure what is really wanted to be virtualized? The entire machine? The OS? Software within the OS? What other features are needed? These are some questions I would like to hack out with others so come join in the foray.

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By: ab

November 12, 2009 4:10 pm

ECMAScript/JavaScript Development Without a Web Browser

Have you ever been coding Java and suddenly wanted to do something using loosely-typed variables or worked out an issue with a little less Java-ness? Have you ever wanted to take advantage of the familiarity people have with some languages (ECMAScript/JavaScript) while still using something that is not a web browser as an environment? Have you ever wanted to debug your JavaScript without refreshing a web page and your cache that just won’t seem to ever refresh properly for you? This and more will be covered today with practical examples in both the Novell Identity Manager (IDM) and Novell Sentinel applications plus any other Java-based applications that you may have around your own environment.

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By: ab

October 8, 2009 4:27 pm

LJDT: The 'watch' command

Do you ever find yourself running a command, pressing the up-arrow, then [Enter], then the up-arrow, then [Enter], then the up-arrow…. this is a great exercise that will get your fingers used to typing random odd key sequences without your eyes paying attention, but otherwise it’s a complete waste of time. A command I have come to love helps me point my OCD tendencies to other pointless tasks while running commands over and over for me. Introducing ‘watch’, because Linux Just Does That.

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By: ab

September 28, 2009 4:13 pm

LJDT: Base64 Encoding

In computing there are two terms which are often confused: encoding and enciphering. One of them, with ‘cipher’ in its name, usually best refers to something that is cryptographically enciphered which means it was mathematically mangled in a fashion that the result, regardless of the input, is fairly random, patternless nonsense to the un-key-assisted eye. The other term refers to simply changing data from one form to another at is basic level. One type of encoding is ‘base64’ encoding, which is used through many areas of computing and can be explained much more-simply than most cryptographic cipher functions (in my opinion). This article is to show how, on many levels, Linux Just Does That.

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By: ab

September 8, 2009 1:54 pm

LJDT: Workspaces

For a while now I have taken for granted the marvelous functionality commonly referred-to as “workspaces” in the X window system. Anybody using a graphical interface with X already probably has this functionality present by default and in many distributions the feature of multiple workspaces is even enabled by default The idea behind this article is to show how efficiency in the GUI can be improved using this feature and the ease of adopting the technology to suit your needs out of the box, because Linux Just Does That.

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By: ab

August 21, 2009 2:20 pm

LJDT: Installed RPM Size

Sometimes I find myself wondering how big an installed RPM’s files really are. Use a simple script to do all of the calculating of file sizes, plus see how to recreate the RPM from the system where the package is installed in the latest addition to Linux Just Does That.

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