A new form of Comment spam? – url shorteners and redirection?

This is interesting. This blog just had a comment which, at first glance, looked normal.

URL redirection can hide the destination, not always a good thing
URL redirection can hide the destination, not always a good thing

The link first runs through URL shortening service tinyurl.com.

That in turn redirects it to adfly (http://adf.ly) which is where it becomes interesting.
Example of an Adfly landing page
Adfly is an advertising system. Instead of linking directly to the destination, you link with a custom link from them. Before the visitor can go to the new page, they see an advert.
They can interact with that advert or click the big “Skip Ad” button at the top of the page.
If people click on the advert, whoever created the link gets a commission.

I don’t have a problem with Adfly. I’ve seen my son skip the adverts lots of times when he’s getting plugins for Minecraft. What I hadn’t seen before was this method of hiding the adfly link and as far as I know, it’s the first one posted on my blog.

Is it a problem?
I don’t think so, just an observation. It means I’m going to be less trusting of any url shortening from now on.

Is it an opportunity?
Not for me, at least not yet.
It would not be difficult for me to write some code that redirected all my off site links via adfly, including those posted in comments. It does mean anyone visiting and following a link would have an extra step to go through and I’d rather not do that readers.

I used to have google adverts on the blog but when I came to update WordPress I didn’t bother rewriting the templates or installing any plugins. The revenue it was generating was trivial.
I suspect Adfly revenue from this site would also be too small to be worth the effort.

Peer to Peer downloading (Torrents) and network problems

Recently my parents had some friends visit. They had a laptop with them and asked to use the internet. We’ve not problem with that so let them connect…. except when they connected they were running a peer-to-peer file sharing program.

If you’re here, you probably know what that is. A way of sharing large files by turning it into lots of small pieces and allowing all the people who that file to share a little piece with you, until you have the whole file. Then you can share your little pieces with other users.

The advantage of peer-to-peer file sharing is the originators don’t need to have and pay for a server with lots of capacity. Used properly it’s a great idea. In the past I’ve downloaded and shared Ubuntu and OpenOffice files this way.

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My parents house is connected to the internet via our office. I was trying to set up a server and getting very confused as to why my connection kept dropping. It was making a difficult task impossible. I noticed other things like web pages taking longer than usual, or being sometimes fast and sometimes slow. I check the router and realised what was happening, so I blocked my parents guest completely.

That wasn’t enough to solve my problems though. I eventually gave up setting up the server and did it from home in the evening. The problem with torrents is the computers looking to you for little pieces ask for them hours after you’ve stopped advertising they can have them. This screen shot showed my problem clearly – this was taken AFTER I’d blocked the computer at 10.18.6.56. Essentially they’d invited DoS attack. 11,000 incoming connections was more than enough to ruin our ADSL connection for everyone else on the network.

Sure, we could still email, see web pages slowly, but everything was so much harder than it needed to be.

Moral of the story: If you’re a guest with us, please turn off any torrent software before you connect.

Bad Bot go away!

Sigh. Here I am at work on Tuesday morning. List of jobs to do being interrupted by our web server triggering over load alarms. Actually, it’s been doing it for quite a while, but I’ve never sat down to analyse the logs to find what’s happening to trigger the alarm (our gandi.net virtual server is more than powerful enough to cope, so fault finding has been low on my to do list). This morning as I walked to work I saw an overload message arrive in my email. The sun is up, the sky is blue, it’s 8am. It feels a good day to fault find…

It didn’t take long to find the problem. I used grep to pull out todays log entries from the apache log and put them into a temporary file

me@server4:/path_to_logs/rkbb.co.uk$ grep ’06/Apr/2010′ apache-log > check.txt

The bot causing the problem has a user agent of “Mozilla/5.0 (compatible; Purebot/1.1; +http://www.puritysearch.net/)”, going to puritysearch.net I find a ‘search engine’ that doesn’t appear to do anything but display adverts disguised as search results.

So, how to stop this bot. Nice bots read a file called robots.txt which tells them where they’re allowed to go. Purebot didn’t read the robots.txt so I couldn’t excluded it there.

My next thought was to use apache to exclude the user agent. After an hour or so of trying I gave up with that (it is possible, I just didn’t figure it out and took the easy for me approach). The site is running Coldfusion (actually BlueDragon) so in the Application.cfm I can check the user agent and stop processing requests from Purebot there.

<cfset useragenttest = find(“Purebot”,#cgi.http_user_agent#)>

<cfif useragenttest GT 0 >
  <p>Purebot banned</p>
  <cfabort>
</cfif>

The code isn’t my most elegant but it works. Next time I come across a badbot (or Purebot changes it’s name) I’ll just updated this piece of code to ignore their requests.

Gmail default contact for a friend with more than one email address

This is so I don’t forget, it took me a while to not find the answer via google, guess the solution successfully, and then read the solution by chance while looking at something else.

I use googlemail (actually, google apps but let’s not get pedantic).
I have a friend with several email addresses, (work, other, home, other, other).
Recently she asked for emails not to go her work address (unless they’re really urgent).

When I use gmail to write an email just to her, it’s easy to choose which address it’s going too (and I know roughly which address is most appropriate at the time), but I have a contact group set up with her in it and those emails were always going to her work address.

There was no option when creating the group to choose which of her email addresses should be used by default. The address being used (work) was also the address that came up first when composing a message and including her specifically.

I guessed that this apparent default email address was the first contact address I’d entered for her and when I checked it was showing on the top of the gmail list of addresses for her contact record. I replaced the top of list email address with the prefered ‘other’ address, added the work address to the bottom of the contact list. Created a new email and using the contact group and gmail used the ‘other’ address’ instead of her work address.

I later read ‘googlemail defaults to using the first email address of a contact….’

Googlemail down :(

277-googlemail-down-thumb-300x142-276.jpg Googlemail is down 🙁 Looks like they think they’ll be an hour. At times like this I think ‘if only there wasn’t so much spam I’d still have my email on my own server, that’s working fine”. Then I remember, I’m pretty sure the googlemail server uptime is higher than my server, and seeing as I haven’t had to spend any time updating this, that and t’other software to make gmail work, I should be patient and wait for my gmail to return to service.

Moving to a new web server

For many, many years (well, since 2004 which is a long time for internet things) my web server has been at Rackspace. Well, I say ‘my’ web server but in reality it’s their web server, dedicated to just my use and fully managed by them.

They’ve been great. Small amounts of downtime, answering the phone at 2am to help me fix things I’ve broken, swapping out faulty hard disks, power supplies (twice). They are however very expensive and as my server needs haven’t grown as fast as computing power, I can now save some money moving onto a virtual server. The theory is that the hardware down time wont happen on the Virtual Server. My rackspace server has a single disk, single power supply. Multiple disks and power supplies cost a lot of money so the chance of failure was worth taking. Now though, servers are powerful enough for the resources to be shared across multiple users so we all benefit from RAID 60, multiple power supplies. If my needs change (EG a lot more visitors than currently stop by) then the Virtual Server can be moved to another physical server without any noticeable down time, where it can have more resources (bandwith/processor/disk space etc).

So, this week I’ve signed up for 8 shares on a server with ‘gandi.net‘. They’re a web host based in France so close enough to the UK to retain network speed (all the other good virtual hosts seem to be in America). I was a little concerned about not having my trusty 24hour phone number but I’ve just had my first email support call answered very quickly. I couldn’t get a piece of software to install (IP tables) and it appeared to be an issue with the Xen Vitual host setup. I emailed and the resolution came back within 2 hours. I decided to install the latest Ubuntu 9 server which they only released last week, so I was no doubt the first to come across the problem. After emailing me, they posted the solution in their forum and wiki. Great!

I might write some more on the move later but as you might be able to tell from the lack of posting lately, I’m really busy with other things. At the moment at least, Gandi looks great.

Eurocon 2009 – More than just simulation

You might imagine that the Eurocon is a group of 40 grown ups playing computer games and drinking beer. Well, that’s only part of what’s going on. This morning 4 of us went to the local indoor snow ski slope. At about 500m long and kept at a steady minus 7 degrees, it made a nice change from the heat of all the computers in the con room. It appears that after 8 years of no skiing, I still remember enough to be comfortable zipping down the slope.

I’d write more, but I’m quite tired now. Before you ask, I didn’t stay up until 3am unlike many others. I was too exahusted from the journey so went to be around 11pm. Maybe I’ll add to this when I get the photo’s off the camera.

Learn french in 10 days…. assuming you don't need sleep?

My French prof runs an email list of… well, a mixture of humour, observations and such, the sort that many people forward to your email. The good thing for me is that a lot of it is in French and try as I might, I often have to really work at reading it.

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If I don’t understand a word, I’ll open google and translate it. If I still don’t understand it, I’ll translate a sentence. One word in the last email was “entuber”. Google didn’t know the english translation so I search the web. Entuber = to con, apparently commonly used though colloquial. The web site I found the answer on had an advert to “Learn French in 10 days”. Well, clearly I’ve not been trying hard enough. I followed the link to find out more (always looking to improve, to think I’ve spent years trying, on an off, to `parler en plus francais` [Sic]*) so I had to find out more.

The course contains a very comprehensive ‘More than 200 hours learning’…. Well, I’ve learn’t enough maths to know that 200 hours / 10 days = 20 hours per day of learning. Clearly I’ve been limiting myself by requiring more than 4 hours per day for sleep, eating, washing and such.

*[sic] because I know the grammar is wrong, the spelling is wrong, but that’s how I’d say it. Full marks for effort, ‘nil point’ for grace 🙂

Choosing a web browser – why can't I just put up with the default

My first web browser was Netscape 1.1

I remember sitting in the training rooms of GEC Marconi Avionics sometime in the late 90’s, going through the self study ‘How to use the internet’ course. They were good courses, I spent many evenings learning better driving skills (spotting the hazards) and the most time consuming course of all – how to type. Still, now I can type almost as fast I think. The downside of which is my ramblings tend to digress very quickly, so getting back on track, I used Netscape 1.1 to search for ‘porsche’, because that was the suggested search using Altavista. We’re in pre-google days here, Internet explorer may have been around but wasn’t on the work computers.

Then we move to today and the browser of choice is….. well, I can’t make up my mind. I once preferred Netscape, eventually moved onto Internet Explorer. Then Firefox became my friend until the last year or so where it seemed to keep crashing every time I closed it. Now we have google Chrome. So, time to try them all and see what I think.

Start with…. Internet Explorer.
Always there, installed on my laptop. It does the job but I’ve never quite got used to the new layout of IE7. Tabs were a great improvement, it was those that attracted me to firefox a few years ago. I always have more than one window open, and I much prefer to have them all grouped into one program on my task bar.

Firefox
Firefox is great. I prefer the open source angle. I found it easier to use and faster than IE6 (but that could just be perception). I liked the tabs and it was my browser of choice for a few years. Unfortunately it started crashing on exit. Solution was probably just to uninstall then reinstall from scratch but I never got round to it. Still on my list of things to do.

Google Chrome.
Google should stick to making money from searches. The browser is rubbish. OK, a little harsh. The launch marketing was very clever. The design principles are great (single bar for search or URL input was ever so easy to use). The automatic home page creation of most visited sites and recently closed tabs made usability a breeze. Being able to drag a tab into it’s own window even had it’s uses. Unfortunately there are a few bugs to iron out. Like the “view source” command that should show you the source HTML of the page but actually requests the page again so you get a different source. I haven’t got all the plugins working correctly either, both flash and quicktime seem to have issues. Still, for the basic web browsing tasks it’s OK. Comparable to firefox I’d say. It does win the battle on leaving the largest viewable page area, with it’s ultra minimalist interface. When/if they fix issues like the ‘view source’ command it may well become my browser of choice, although by then the other players will no doubt improve too.

Safari.
Mac lovers are taking over the PC world it seems. Apple pushed the download through an iTunes update (only got iTunes for wining an iPod). I’m using Safari this afternoon for this blog post. I find the page a little more blurry than all the others. I think there is some ClearText Font Smoothing (insert correct term here if you know it!) but I haven’t found the setting to reduce it’s smoothing. Coming from the land of Mac, this also has a few things done a little differently to the PC way. Not right or wrong, just different. Like the close button being to the left of the name instead of the right. I’m not a fan of the grey shading style of the browser either, but it’s something I’ll get used to.

So, when it comes to desktop browsers which will I settle on?
None of them. I like things from each so will be keeping them all around for different reasons. Use them all for their strengths and switch between them to avoid their weaknesses.

GPS Logging from my PDA…needs a little work I think

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I spent the afternoon of my day off going for a walk. From my house in Faversham I walked to canterbury via some woodland, old villages and the North Downs way. As my PDA has a GPS receiver built in I thought I’d try logging it’s output to see exactly how fast I’m walking nowdays. Last time I checked, walking without a rucksack on clear footpaths and not too hilly, I walked an average speed of 6km per hour.

Well, my first fast analysis of the log file shows I’m going a little faster. It also shows I need to improve my map reading, I certainly don’t remember passing through customs on my way to Canterbury via South Africa and Germany…. hmmm, perhaps there’s something wrong with those logs.

For completeness, I’ll add my PDA is a Windows Mobile 6 HTC Touch Cruise. The GPS logging software is called Sunset from Kharsim.net. The GPX log file sunset created was uploaded first to http://www.gpsvisualizer.com/ and the analysed view came via http://www.everytrail.com/.

I’ll try and spend a little time finding the flawed data from the log then finding a better way of creating route paths and analysis. Everytrail does look reasonably complete from a fleeting first impression and has the facility of hosting the maps so you can zoom in and out. Now, how to find the error lines in that GPS Log and remove them.

To finish on a high, my average walking speed according to my GPS is 3,758 miles per hour. Must dash, I fancy visiting nipping down to the south of France before tea time, should only take me 20 minutes from here 🙂