The Problem

So you've followed all the instructions on installing Tomcat and you're almost ready to create your first JSP web app. Unfortunately, you can't seem to access the web interface for Tomcat even though it's started and Netbeans throws this error:

Starting of Tomcat failed, the server port 8080 is already in use.
See the server log for details.


The truth is, it may not be anything to do with the port number assigned to Tomcat!

The Solution

Here's the scenario: you are developing a web application using PHP on an Ubuntu server. You need to pull in data from an external database as part of the app. Unfortunately, the external database is Microsoft SQL Server. Accessing a PostgreSQL or MySQL database via PHP is very easy, but as I discovered, accessing MS SQL Server is less straightforward.

When you have first installed PHP, you may find that json_decode doesn't work. What will happen is you will be given no output at all. Carry on reading if you would like to know how to fix it.

To determine the symptoms:

1. Enable error messages to be shown by writing ini_set('display_errors', '1'); in your PHP code.
2. Most likely, you will be given this error message now: Php Fatal Error Call To Undefined Function Json_decode

The solution:

This is part two of a two part article describing how to set up Zarafa on Debian using Postfix. The first part of the article covered the essentials of spam and virus scanning for incoming mail via spamassassin and clamassassin. This part covers secure user authentication for sending mail (SASL) and training spamassassin to be better at recognising spam.

This is the first of two articles about configuring Zarafa to enable some extra options that aren't covered in a default install. I've talked a little about Zarafa in a previous article. It's a Linux groupware system that's almost entirely open source. There's some very good documentation, including installation instructions, on the official Zarafa website. However, while this documentation covers Zarafa in great detail, it doesn't cover many common Linux server programs you might want to combine with it.

Zarafa is an email groupware system that aims to provide the capabilities of Microsoft Exchange on Linux servers. It's almost entirely open source, the only exception being an Outlook compatibility layer for business users who are used to Outlook and don't want to switch away.

This one's short and sweet: while working on a PHP application I needed to format some numbers as text so that, for example, '1' became '1st', '13' became '13th', '22' became '22nd' and so on. There isn't a built-in PHP function to do this (as far as I know) and none of the code snippets I came across online were very neat, so I ended up writing my own function. Since it's something that I imagine gets used a lot, I thought I'd put it up here.

As the lack of recent updates might suggest, things have been quite busy work-wise recently! Since I've been working a lot, and since it's Christmas, I thought I'd write something a bit different for this article. While I haven't had much free time lately, I've spent a bit of it playing a game by the name of Trine. It's promoted as a physics based platform/puzzle game, so there is a vague science angle to tie in with the rest of the site!

Overall I found Trine a lot of fun, with beautiful graphics, great voice acting and some really fun levels. However, it's a little let down by some minor bugs and glitches in the physics. Personally I enjoyed it a great deal, but hardcore gamers might find it a little too short and on the easy side.

A friend was having some trouble with the Netgear wireless router he was given by Virgin Media, which I fixed by replacing the Virgin-supplied firmware with the latest Netgear firmware. Doing this required a bit of digging around, so I thought I'd write a quick guide to sum up the information I found online.

Like many people, I rely heavily on ssh to maintain and configure computers remotely. However, doing so usually requires making an outbound ssh connection from the computer you're working on, which isn't always convenient. For example, if you're using someone else's computer, the chances are they're using Windows and don't have an ssh client program installed. PuTTY goes a long way to mitigating this problem, but it can't help you if the place you're connecting from has a firewall that blocks outgoing ssh traffic, or if your ssh server is configured to require RSA key authentication.

This is where Ajaxterm and Anyterm come in useful. Essentially, they are apache modules that provide a webpage containing an ssh terminal. So long as you have access to the internet, you can then go to this webpage in a browser and use it to log in to your system using ssh.