logalert

Very often we go through logs looking for certain messages (hopefully using grep), just to execute a certain action afterwards.

In such case, logalert may come of help. It is a log file monitor tool which executes a specific action or script, whenever it matches a given string (pattern). You can even use the matched string in the action, such as a parameter to a script.

Using diff and patch

Using Diff and Patch tools

Creating the patch

If you want to port some changes from one source directory to another, you can use diff and patch. First you create a file which contains the information of the changes, so called patch. This can be done with the diff tool, or if your code uses Subversion, then you can use the svn diff command:

$> svn diff > changes.patch

Applying the patch

Then you can copy this patch to another source directory where you can apply it using the patch tool:

$> patch -p0 < changes.patch

Mind the -p0 option. It indicates to interpret the directory structure just like the one where the patch was generated.

Undo

If you test the patch and you decide you want to remove it, then you can do it from the same directory where you applied it with:

$> patch -R -p0 < changes.patch

More information

• Check the man pages of diff and patch tool.
• LinuxToday tutorial

VMWare and Xen Management with BixData

Manage multiple hosts running VMWare and Xen with BixData

BixData - http://www.bixdata.com/

Distribution for Parallel Clusters

Another distro arrived to the land of parallel linux cluster computing.

ParallelKnoppix - http://parallelknoppix.cebacad.net/

Course Management System

http://moodle.org/

Where did my disk space go?

Sometimes I wonder where all my disk space went. It's not that I have much of it, it is simply that I don't have a clue where did it go. And the more I free up, the more it keeps on disappearing.

Well, Filelight is the answer. It scans any directory, even remove ones, and displayes the usage in a comprehensive, zoomable, pie chart.

Suddenly, there they were... the forgotten files that were eating up my disk space... squash... squash... killed!

uniq

Uniq is a not so well known command from the GNU Coreutils which removes duplicate lines from a sorted file. FYI, sorting can be done with... sort!

Simple Backups

One of the Google's 2005 summer code products, sbackup, is a simple backup tool that will allow any newbie to backup its own data with simple steps. Read about it here.

Very interesting, but of course quite limited. If you are interested in full featured backup solutions for Linux, UNIX and Windows(!), I suggest bacula.

A simple coincidence?!

Recently, Peter J. Quinn, director of the state's Informational Technology Division, is at the center of the decision to require that all documents produced by the state of Massachussets executive branch are to be stored in a new open standard format, called Open Document.

Some days ago, the administration has launched a review of several trips by Mr. Quinn to conferences out-of-state.

Nothing to be worried about in a democratic state that struggles everyday to fight it's own corruption.

All plain normal.

Nothing to see here. Move on ... Move on... Just a routine investigation ...

Pure coincidence?

Read this article.

On virtualization and the x86 arch

"Forget the OS, it's x86 that's important" is an interesting article about virtualization and a new Sun's approach: Containers.

Read it at TechWorld.com

Some security principles

Newsforge as published an interesting article about security.

The words of the Prophet...

You may find the words of the prophet Stallman here.

Read them so you may FREE yourself...