Peter Lieverdink (also known as cafuego on IRC/identi.ca, engineer on OurDelta builds and for Open Query) has co-authored a book that’s available since Monday. The title is Pro Linux System Administration published by Apress.

These days some people don’t want to bother with system administration, and either hire or outsource. Others want to find out more and do things themselves (home and small office use), and that’s the intended audience for this book.

Thanks to Days of Wonder the company I work for, I’m proud to release in Free Software (GPL):

mysql-snmp – monitor a MySQL server with SNMP History

At Days of Wonder, we’re using MySQL for almost everything since the beginning of the company. We were initially monitoring all our infrastructure with mon and Cricket, including our MySQL servers. Nine months ago I migrated the monitoring infrastructure to OpenNMS, and at the same we lost the Cricket MySQL monitoring (which was done with direct SQL SHOW STATUS LIKE commands).

I had to find another way, and since OpenNMS excels at SNMP, it was natural to monitor MySQL through SNMP. My browsing …

When I wrote my previous post titled all about storedconfigs, I was pretty confident I explained everything I could about storedconfigs… I was wrong of course

A couple of days ago, I was helping some USG admins who were facing an interesting issue. Interesting for me, but I don’t think they’d share my views on this, as their servers were melting down under the database load.

But first let me explain the issue.

The issue

The thing is that when a client checks in to get its configuration, the puppetmaster compiles its configuration to a digestible format and returns it. This operation is the process of transforming the AST built by parsing the …

Since a long time people (including me) complained that storeconfigs was a real resource hog. Unfortunately for us, this option is so cool and useful.

What’s storeconfigs

Storeconfigs is a puppetmasterd option that stores the nodes actual configuration to a database. It does this by comparing the result of the last compilation against what is actually in the database, resource per resource, then parameter per parameter, and so on.

The actual implementation is based on Rails’ Active Record, which is a great way to abstract the gory details of the database, and prototype code easily …

In the previous post of this series we installed and set up VirtualBox. We prepared it for a default install of CentOS 5.2. This time, we cover the installation of the OS itself. Changes since the last article are an upgrade from v2.0 to v2.1, and the fact that I’m running VirtualBox on my Asus [...]

Since a few months we are monitoring our infrastructure at Days of Wonder with OpenNMS. Until this afternoon we were running the beta/final candidate version 1.5.93.

We are monitoring a few things with the JDBC Stored Procedure Poller, which is really great to monitor complex business operations without writing remote or GP scripts.

Unfortunately the migration to OpenNMS 1.6.1 led me to discover that the JDBC Stored Procedure poller was not working anymore, crashing with a NullPointerException in the MySQL JDBC Driver while trying to fetch the output parameter.

In fact it turned out I was plain wrong. I was using a MySQL PROCEDURE:

DELIMITER //
CREATE PROCEDURE `check_for_something`()
READS SQL DATA
BEGIN
SELECT …

One of the first things we had to do here at OlinData is set up a testing environment. Many customers have many different OS environments and we want to be able to accomodate all of them. With the setup described here, we will be able to easily set up many different OS’s, regardless of the [...]

I've updated MySQL Query Profiler, which I consider the most important tool I've written. It's now included as part of the MySQL Toolkit project on Sourceforge.

I've just released MySQL Duplicate Key Checker on SourceForge. This is a complete rewrite of a tool I initially released under a slightly different name. It is now much more powerful and friendlier to use, especially for scripting, and has many more options.

MySQL Table Checksum is a tool to efficiently verify the contents of any MySQL table in any storage engine. You can use it to compare tables across many servers at once. The output is friendly and easy to use, both by eyeball and in UNIX command-line scripts. The provided MySQL Checksum Filter helps you winnow output so you only see tables that have problems.