Linux System Admins Blog

The error message in the title occurs in a combination of circumstances. If you have 2 MySQL databases, one master and one slave in a replicating setup and you use triggers you may encounter this error. Although it is not necessary for the slave database to have the same users as the master for replication [...]

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The CentOS team just released their latest version of CentOS-5.2, a minor upgrade for the Centos-5 release. This is based on the upstream release RHEL 5.2.0 and includes packages from all variants including server and client repositories.
Any system running CentOS-5 (either 5.0 or 5.1) can be upgraded by just running:
yum upgrade
that will bring in the [...]

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This post describes a way to implement data encryption in the front-end of an application and how to make it compatible between a PHP front-end and a Java front-end.
First off we need to decide what type of encryption to use. AES is an encryption standard that has been endorsed by the NSA and is generally [...]

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FFMPEG is an open source application that allows you to convert video and audio files easily between a variety of different formats. It supports most industry-standard codec and can convert from one file format to another quickly and easily. This guide is intented for the installatiion of ffmpeg, ffmpeg-php, mplayer, mencoder, lame mp3 [...]

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Considering that you have an existing php installation compiled from sources, it is very easy to add afterwards new php modules, outside the php binary. This can be achieved without any interruption of the web services, and requires just the following steps:
1. Ensure you have the mcrypt libraries and development tools.
For example on a rhel [...]

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PrometHost offers best of class hosting for websites, databases, and other services such as email, domain registration, spam filtering, etc. We have recently made a decision to focus on three things for our hosting offering:
- security
- [...]

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Any host or system admin hates the words “its not working” or “its down”. When I see a big site take a hit or is town there are two reactions that I generally have:

Site Down – those poor bastards (system admins) their life must suck right now
Site Down – SEE!!! It happens to them [...]

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To install Subversion (SVN) login to your server (shell) and execute:
yum install subversion
If perl-URI is not installed edit /etc/yum.conf and remove perl* then execute:
yum install perl-URI
Restore perl* on /etc/yum.conf.

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To install Wordpress with Subversion you need shell access to your server and have Subversion installed. To start, login to your server (shell) and go to directory where you want to install Wordpress and execute this command:
svn co http://svn.automattic.com/wordpress/trunk/ .
Copy wp-config-sample.php to wp-config.php. Edit wp-config.php and enter database details. Access your [...]

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