Tutorial: reconfiguring virtual hosts after upgrading to Apache 2.4.7 on Ubuntu – what you need to change


Once upon a time, I was running Apache 2.2.22. I had set up my virtual hosts by making up some fantasy domain names for each of my sites, such as drupal.kevin. I would then edit /etc/apache2/vhosts.conf to add information about my DocumentRoot, DirectoryIndex and CustomLog for each of my sites. Because I wanted to make sure they were always backed up properly, I kept my websites in my /home folder rather than /var/www/html, which meant I also needed a symlink from there to my websites directory. Lastly, I would add a line for every virtual host in /etc/hosts, such as drupal.kevin

So far so good. Unfortunately, all that stopped working after upgrading from Ubuntu 12.04 LTS (Precise Pangolin) to 14.04 LTS (Trusty Tahr)… Continue reading

Tutorial: Cryptswap1 errors, wonky monitor displays & how to fix things after an Ubuntu 14.04 upgrade

Last week I ran into some serious problems with my Ubuntu 12.04 after some routine updates. I wasn’t able to determine exactly what happened but it was related to one of our usual suspects, the cryptswap1 error at bootup, which announces that ‘the disk drive for /dev/mapper/cryptswap1 is not ready yet or not present‘.

I tried various things suggested in forums, including this one. Unfortunately, due to a slightly different config, this culminated in me somehow partially disabling my swap space. I happened to have a Debian Live CD lying around, so I proceeded to do a harddrive backup (mainly to rescue that morning’s downloaded emails), but that was tricky because my /home folder was encrypted. Though I am told it is possible, I didn’t have the time on top of all this to go & read up on how this could be done via a Live CD!

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GIS web mapping portfolio site

I can’t believe it’s been two years since I last made an actual blog post! In my defence though, I was pretty busy last year getting my portfolio site up and running – and on 20 November 2013 it went live.

Everything on this site right down to the PHP was made by me and has all my GIS web apps to date, starting in 2009. Most of the projects have either had a historical or a global development-related theme. Click on the image below to take a look:

dangeographics GIS web portfolio

my web mapping projects

Update: In 2016, I took down my PHP site and moved many of my maps to my github pages, because I wanted to enable people to have a look at my code. The link now redirects to the new site.

A week of (un)conferences… – part 1

This year has started well for me. At the end of January I was at RewiredState’s SocTV Hackday (Education-themed) and my team won the Switch-over award. Hardly a month later, I come across a whole week of relevant events in London that I really want to go to. I decided to bite the bullet and get an eyewateringly-priced 7-day Travelcard, just to get the accomodation issue out of the way.

The only reason I even knew about the Dev8D un-conference was from the events page on the OSM wiki. It’s for developers working in education and the idea is to have a core skills session in the morning, a lunchtime meetup and then a more specialised module in the afternoon, followed by an ‘open session’. If you wanted to be involved in a particular challenge such as Jorum, you could hang out in Basecamp (conveniently equipped with a perpetual buffet of the usual geek delicacies such as chocolate bars, biscuits, crisps and cola). As before, I’m just going to write up a selection of the most interesting sessions I attended:

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Second Open Source GIS conference, Nottingham

Open Source GIS (OSGIS) was something I’ve always been intrigued by from an early stage in my GIS degree. Not only because of its significance for developing countries and non-profit organisations, but also for its participatory development (and to find out whether this actually works well).

The second UK OSGIS conference, 21-22 June 2010, was different from most of the academic-centred conferences I usually go to as most of its participants seemed to be drawn from the industry/public sector. The first day had a range of full-day training courses to choose from and true to my vocation, I went for web mapping workshop. Using a Linux live CD to trick the university’s Windows workstations, Jo Cook from oaDigital gave us a crash course in how to get spatial data onto a website. We started off by loading data into a PostgreSQL database and then displaying it in QuantumGIS, a desktop GIS. where we where able to perform some spatial queries. Moving on to MapServer, we learned how to visualise layers of map data in a browser by using the correct map file syntax. Once this was mastered, we could use php to create our own web maps with the OpenLayers library – not only to display various layers but also elements such as zoom controls and custom viewboxes.

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Tutorial: using an IDE-to-SATA converter to install a second hard drive

the scenario: one day you stumble upon a box containing a brand new Maxtor 6Y080L0 IDE hard drive. You vaguely recall buying this in the year 2002 but it never got used for anything. You don’t really want give it away either, as it boasts a useful 80 gigabytes…so you decide to bite the bullet and attempt to install it in your PC. The only problem is, technology has moved on. You open your case and discover that your snazzy state-of-the-art motherboard sports a dizzying amount of SATA connectors – but only one IDE connector. That would be okay except for the fact that this connector is already occupied by your CD/DVD writer. Along with trying different jumper switches and drive combinations, daisy-chaining two IDE devices to this connector just won’t work.

the solution: rather than buying a new SATA harddrive and ebaying the old one, you purchase one of those handy little SATA converters for a fraction of the price. The plan is to attach it to that pesky IDE hard drive so that you can effortlessly hook it up to the SATA connectors on the motherboard.

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