Tutorial: Writing a simple WordPress plugin from scratch

6th October 2014 by Steve Whiteley

In this introduction to WordPress plugin development, we will create a plugin called Teletype that packages the jQuery Teletype Plugin into a WordPress plugin. Teletype is a jQuery plugin that types out text, and then optionally deletes it, replicating human …

WordPress Survey Quiz Tool Plugin is back!

16th June 2014

I’m pleased to announce that we have updated and re-released the very popular WPSQT plugin. It’s a highly customisable Quiz, Survey and Poll plugin to which allows for unlimited questions and sections – perfect for running an exam website or …

CatN’s Network Time Protocol Network

28th January 2014

Time is important, especially when it comes to computers serving time-sensitive data. There is of course a very well established means of keeping computers in-sync with each other, indeed it’s one of the oldest protocols still in use on the …

Racing to launch with ArduSat

24th June 2013

A few months ago CatN became the sole platinum sponsor of the ArduSat satellite project on Kickstarter. ArduSat is an Arduino powered satellite which allows the general public to design and run their own experiments in space. There’s a huge …

Working with Virtual Machine images

7th June 2013

CatN engineers spend a lot of time working with virtual machine images. We have put together this useful list of commonly used commands and procedures to help you get started on your next project. For simplicity we assume to work …

Add a virtual storage device to a Virtual Machine

5th June 2013 by Nicola Asuni

Following our previous article about resizing virtual machine images, we now look adding an additional storage device to an existing VM. If instead you wish to extend the existing VM storage volumes, please consult the article “Resize a CentOS Virtual …

Resize a CentOS Virtual Machine Image

3rd June 2013

Following our series of articles about virtual machine images, we now look at a common problem faced by system engineers – what happens when you run out of disk space on your virtual machine? This guide addresses this issue and …

Automated CentOS Virtual Machine Image Creation

28th May 2013

This article shows how to create a CentOS Virtual Machine (VM) in unattended mode using a shell script and illustrates the main steps and options to reproduce the process manually. The following script and commands will create a base image …

Access Control – Are you in or out?

29th April 2013

As CatN continue on our journey towards ISO 27001 accreditation, part of the information security policy requires that we have an active and enforced security model in place at our office location. Since introducing an access control system in June …

Create an OpenStack instance with just Curl

23rd April 2013

For some reason, the idea of direct interaction with the various OpenStack components seemed like a good idea. The aim was to create an instance, set sane security rules, and add a public key all through the API. I struggled …

Building a virtual machine image for CentOS

18th April 2013 by Joe Gardiner

This post describes the process of creating a CentOS virtual machine image. Creating a base or master image is incredibly useful in a cloud environment as it allows the creation of multiple nodes / VMs or guests based on the …

Advanced PHP error handling in the cloud

8th April 2013

LogPipe is a PHP extension module that extends the default PHP error messages with additional information and allows you to pipe the logs to an external program or write them to a syslog facility. When a user connects to a …

Unit Testing WordPress Plugins: The Right Way

17th August 2012

Whether you are currently writing a WordPress plugin and have decided to embrace unit testing or you are about to begin development of a plugin and want to unit test it from the start, learning how to do it correctly …

TCPWebLog – Collecting and Aggregating Web Logs on the Cloud

15th June 2012

TCPWebLog is a Free Open Source Software system to collect and aggregate Web-type logs (i.e. Apache, Varnish, PHP, FTP …) from multiple GNU/Linux computers running on a Cloud. When a user connects to a Website hosted at CatN, the response …

How to create TCPWebLog RPM packages for Enterprise Linux

15th June 2012

This is a short hands-on tutorial on creating TCPWebLog RPM packages for Enterprise Linux, including, but not limited to, Red Hat Enterprise Linux (RHEL), CentOS and Scientific Linux (SL). TCPWebLog is a Free Open Source Software system designed to collect …

DevOps Ninja Assassinates Web Logs!

1st June 2012 by Ben Kennish

Hello, I’m Ben and I recently joined the CatN team as a Systems Engineer / DevOps Ninja. My first proper task was to get statistics working for two sites hosted on an early alpha of vCluster version 2; housepricecrash.co.uk and …

ServerUsage – Measuring users’ activity on Linux hosts

24th May 2012

ServerUsage is a Free Open Source Software system to collect and process usage statistic information from multiple computers running a GNU-Linux Operating System. Since CatN is a “cluster” hosting company, one of the challenges is to track and analyse the …

How to create ServerUsage RPM packages for Enterprise Linux

23rd May 2012 by Nicola Asuni

This is a short hands-on tutorial on creating ServerUsage RPM packages for Enterprise Linux, including, but not limited to, Red Hat Enterprise Linux (RHEL), CentOS and Scientific Linux (SL). ServerUsage is a Free Open Source Software system to collect and …

How to create SystemTap 7 RPM packages for Enterprise Linux

22nd May 2012

This is a short hands-on tutorial on creating SystemTap 7 RPM packages for Enterprise Linux, including, but not limited to, Red Hat Enterprise Linux (RHEL), CentOS and Scientific Linux (SL). “SystemTap provides free software (GPL) infrastructure to simplify the gathering …