Matt Daubneys Blog

Next week I may not be around so much. I’m off to Cambridge to do a week long CCNA course. This is going to be hard going at 12 hours a day for 6 days, but should be very rewarding.
Why am I doing this to myself? Well, I need a job, and it’s very hard to distinguisj yourself from the current crowd, so I believe that achieving a CCNA off my own back should help prove how determined I am to progress in an IT environment. I’ve been going through and making notes all over the prereading today, and it doesn’t seem too bad. It’s going to be a bit of a push on my memory, but I believe it’s do-able.
It’s a little bit daunting I will admit, this being the first professional course I’ve enrolled on since I finished Uni. Hopefully the people will be as nice as the Ubuntu community.
If I’m slow to respond to anything this coming week, I apologise and will get on to it asap once I get back.

I’ve been playing with a velleman k8055 USB experimentation boad and think I’ve finally come up with a use for this first board. I’m going to attempt to automate a few things in my room using a Linksys NSLU2.

The first thing to attempt is a nice simple one and does not involve touching any household electrics. A simple motor arrangement on the curtain rail to open the curtains in the morning and force me to get the hell out of bed!

The second thing I intend to do with it is a little more complex and will require some more research. I intend to somehow replace the dimmer switch in my room using the analgue output from the board. If anyone has any good references on what I need to read up to do this, let me know!

Well, now that Uni has finished, I need a job. Having been doing a Physics degree at Swansea, I’ve more or less come to the conclusion that I don’t really want to go into a Physics field, and would rather move across into a computer networking position. This comes with a few problems. Firstly, I have no professional experience with this kind of work, I do have lots of amateur experience, having networked my house and helped administrate the University Computer Societies network. I have been exploring the option of doing a CCNA to give me a kick start into a career, but these are expensive.

Why does this mean anyone should hire me? Well, I’m incredibly eager to learn. Having no professional experience means I will have to learn fast, and I fully intend to do so. I’m more or less convinced I want to do a CCNA, to the point where I’m willing to fund it myself and just need to find the funds to do so. I have heaps of experience with Linux servers, I’ve administered several for friends over the years and attempt to help people fix their Ubuntu machines in #ubuntu-uk and on the ubuntu-uk mailing list. I also have experience mending windows machines, again largley for friends and family. I am incredibly enthusiastic and really want to get on and work, having been sat on my bum for the past 2 weeks just applying for jobs, I’m now reaching the point where I just want to get on and work. I’m reliable, hard working and eager to get involved.

My CV can be found here in pdf and here in MS Word format, so if anyone has any opportunities going, please let me know!

I’ve discovered recently that I don’t sleep well if I sit on the internet too late at night. Here is my solution.

I’d been intending to learn Lua for a little while now, so this entire project was written in lua, with some bash scripts to call stuff. Essentially what it does, is every minute it checks the time. If the hour is greater than or equal too that set in /etc/bedtimer then it uses iptables to close all the ports I use that go out to the internet. This allows me to continue using my local network stuff (except ssh) if I had things like coursework to do. The server part continues to run every minute after that, incase I try and override it (bad me). There is also a gnome bit that is loaded when I log in. This part simply uses the ubuntu notify-send thing to warn me when I have 15 minutes before the net shuts off, and when it shuts off.

The bit that does all the work is loaded at boot using an initscript. I have yet to reboot and test this, as it’s my first initscript, but it looks ok

Hopefully this will force me to actually stop wasting time on the net in the evenings and actually go read a book or do something to wind down at the end of the day.

The files can be found here. There is a shell script to install it all, but it’s rubbish and may not work on your machine! BE WARNED!

My knowledge of linux is sadly lacking, but every day I improve on it. Since I had a few days free over the easter holidays I thought I’d try and improve this further by installing Linux From Scratch. This is essentially building up a linux system from it’s base packages and takes a LONG time. This to me seemed like a good idea, it would exponentially increase my knowledge of what makes linux tick, and what depends on what.

I started on Monday night by reading through all of the LFS documentation. As bedtime reading goes, it’s actually quite interesting, and it seemed like a good idea to get an overview of what needs doing before I started.

Luckily for me my laptop has a fairly large HD (320GB) so finding some space on a partition was quite easy. A quick boot into a livecd and resizing my /home partition created a nice little 10GB partition for LFS to go in. That was at 9am in the morning. By 10:00am I had downloaded all the required programs in the mounted partition as directed by the book and started to build them.  In the first day, I managed to build the initial toolchain and got into the chroot and got to chapter 6.15 in the LFS PDF. The longest thing to build was probably either glibc or GCC, which took just over an hour, but did give me time to cook some tortillas from scratch for lunch

The second day, it took me from about 10 in the morning till roughly 3 in the afternoon to finish installing everything.  Was a bit quicker than I expected, but also a lot more involved.

I did hit a few roadbumps, I didn’t have gawk installed on the host system, so at one point something didn’t compile properly and freaked out a bit. A simple sudo aptitude install gawk fixed that though. When I was recompiling glibc all of the tests failed, it took me a few minutes to realise that the reason this was happening was because I’d forgotten to run “make”.. oops.

The last major bump was that when I chose which options to compile with the kernel, I forgot to add the drivers for my ethernet card and my wireless card, so when I booted the machine I had no network! A quick scan through the options and a recompile sorted that out (to include the b44 driver)

What have I learnt from this? Two things mainly.

1. Where everything should live on a linux system and why its there
2. Package Managers are beyond fantastic. They save so much time and hassle!

Tomorrow I intend to try and make my LFS install useful by installing openssh initially, wget and possible x.org and gnome. That may be a bit ambitious at the moment though!

One of my modules has recently involved writing a set of monte carlo models. I’d heard of these mystical things before, but never implimented one myself (or understood the statistics behind them). I’ve become fairly interested in how these things work now, but one thing I didn’t understand was how the number of random numbers you use affected the final result. This seemed like a fairly easy thing to calclate and graph, so I bodged som outputs into my code, wrote a short python script to do a few hundred runs and see what came out the other end.

What came out, I really wasn’t expecting. I assumed the uncertainty (or variance) would decrease as an exponential curve as you incresed the iterations, what really occurs can be seen in the graph below.

WTF?

That horrible wiggly bit at the beggining was completley unexpected. I am now wondering if it’s a sign that my data hasn’t been thermalized properly.

Any one out there with any experience of this want to comment?

Over the past couple of months I’ve found myself becoming sluggish, and very slow at completing various tasks. This all reached a peak when I found myself unable to sleep a lot of the time so just over a week ago I went to the doctors. Since then I’ve been diagnosed with depression and put on some anti-depressents to try and alleviate things a bit.

The problem I have now is that I have lost my work ethic because of the past few months of lethargicness. I’ve now also found it relativley difficult to actually get out of bed in the mornings. In order to try and rectify this I am giving myself a couple of challenges.

1. Be up everyday by 8am
2. Go for a walk every day
3. Regain my work ethic and concentration by sitting at my desk and working for at least half an hour before a break
4. Take a decent photograph every day next week (Mon -> Sun)

As far as I’m concerned, 1 and 3 will be the most difficult, however they’re the most important in that list as it stands. Each day I’ll try and post a progress report, and my photo of the day.

I went wandering this evening after being a bit restless, so decided to try out my new camera (a canon EOS 1000D) on some nice landscapes. Not being very good at photography in general I was quite pleased with the results.

I think in this one the sun was a bit too bright, there maybe someway to filter this out, but I’m unsure.

This one is my favourite. The nice warm glow from the clouds and in the wet sand is amazing. Might have another go if we get another dry evening before christmas

After we’ve had a few issues with Virgin Media, I decided it was time to take the plunge and find out if it was us or them. The simple way to do this was to measure the amount of bandwidth we use during a day, see if we exceed their fair use terms for the cap to come into effect. I also wanted to throttle people using Bittorrent in the house, so it was time for a network redesign! Out came Dia and we end up with this.

Once I had a network design, all I had to do was put together an old, low power box and install IPCop. The first box I built had a duff motherboard on it, and the second one didn’t like one of the three network cards I was feeding it. A little fiddling around and I had a working box. Turned it on and it sounded like a 747 taking off. The solution to this was simple, a quick clean with an air duster and an application of spray grease on the fan spindles. This solved the noise problem quite nicely and allowed me to continue on to install IPCop.

The install for IPCop from CD is the same as installing linux in the pre-LiveCD age. You simply follow the onscreen prompts and let it do what it needs to. As in the diagram, I set up a red, green and orange network. I decided this after a bit of reading around the subject on the IPCop site that recommended putting any webservers and the like into the so called orange zone to prevent people from breaking into the trusted green zone. The red zone is the wild wild west of the Internet, so it’s allowed the least access into the house.

Once IPCop had installed nicely I discovered a small problem. My previous network setup had completley relied on DHCP to give out the IP addresses, it turns out that IPCop does not do DHCP in the Orange Zone. A quick google about for some commands and I discovered how to set the ipaddress properly and the nameservers so it could talk to the interwebs properly.

Now I had IPCop set up correctly I clicked on to it and gave everyone a fixed IP, so I can track individuals bandwidth use easily. This was done easily through the GUI. I also set up a transparent proxy in order to play practical jokes easily

The next part was the hardest. How to actually record individuals bandwidth usage. To do this I dug about again and found an addon called Net-Traffic. This gave me oodles of information, but not to the level I was after. A further dig around led me to the idea of adding more rules to ipac-ng. Remembering that IPCop puts ssh on port 222, I shelled in and found the rules file in /etc/ipac-ng/rules.conf. I then added a couple of lines to this such as

#bandwidth by Wii
internet to Wii|ipac~fi|eth2|all||192.168.1.106||
Wii to internet|ipac~fo|eth2|all|192.168.1.106|||

Once this was accomplished, I could check on peoples bandwidth usage by running

ipacsum -t today

which would give todays usage.

I shall give it a few weeks and then look over these nmbers and see just who is eating the internet alive!

So I’ve decided to learn to write C# as I have been repeatedly told that it is a good language (even if it’s designed by MS). So i’ve dug out and installed a copy of MonoDevelop and got started with the Wrox book “Beggining Visual C# 2005″.

I start by writing a simple Hello World application as shown on page 19 of the book, which in Mono looks like the following:

// project created on 9/1/2007 at 8:08 AM

using System;namespace HelloWorld

{

 class MainClass

 {

 	public static void Main(string[] args)

 	{

 		Console.WriteLine("Hello World! My first C# proggy!!");

 		Console.ReadKey ();

 	}

 }

}

A quick build attempt and the first problem comes along with an error of
A quick scout around on Google and I find that MonoDevelop assumes you're writing for .net version 1.1 and you have to change this under Project -> Options -> Runtime Options. Then set Runtime Version to 2.0.

After trying to compile it again nothing happens. A read through the build logs shows that I haven't installed gcms (some kind of mono compiler I assume??) one apt-get install mono-gcms later and everything compiles and runs as it should