A very big Networking LAB – DN42

I’ve always thought of JAWUG¬†as a network lab the size of a city.

But now there’s DN42, which is describes itself as,

dn42 is a big dynamic VPN, which employs Internet technologies (BGP, whois database, DNS, etc). Participants connect to each other using network tunnels (GRE, OpenVPN, Tinc, IPsec) and exchange routes thanks to the Border Gateway Protocol.

I’ve joined DN42, and gone a little crazy with it. So far I have nodes in the US, Ireland, Australia and South Africa. This means I can interconnect with other DN42 members anywhere in the world, having resilience against failures.
I’ll probably be adding more to that, but my first step will be to upgrade my Australian node to something with a bit more bandwidth.

So, get over to http://dn42.us/ and get started.

Getting simple data from MyEskom

Eskom has developed a great webapp it calls MyEskom. Once you create an account and tell it where you live, it’ll give you localised information on the state of the power grid.

It looks pretty good on a phone, better on a tablet, and aweful on a proper web browser.

Its great that they’re making the information freely available, I’m just not keen on having a web page open that hurts my eyes. I want a simple 2-line summary of what’s going on.

So I dove into the background and figured out which HTTP POST to fake to get all the information I needed. Then I wrote a simple python script to do just that, and print out what I wanted to know.

The output I get now is very simple, but it contains everything you need.

Power Status: high/up/red
Turn off: Electric Stove,Geyser,Pool Pump,Dryer,Dishwasher,Heater,Normal Lights

Code is available on github

Feel free to fork it, contribute and make something awesome.

HOWTO: Multicast Irish Freeview (Saorview)

If you’re in Ireland and you’ve been watching TV, you probably know about Saorview and the migration to Digital Terrestrial TV.

Being a geek, I decided that using a TV to view TV wasn’t really the way to do things.
So instead, I decided to find a way of viewing Saorview on my PC.

So the easy way, is to get a DVB-T receiver for a PC, and tune to the channel you want to view. I’m not going to show you how to do this, because the guys at mpeg4ireland already have.

I’m going to show you how to receive every Saorview channel at the same time.
Although I’m sure you’re not going to be able to watch them all at the same time…

Continue reading HOWTO: Multicast Irish Freeview (Saorview)

Seacom problems

Or the alternate title of “Why your inability to access international content is your ISP’s fault, and not Seacom’s”
Or “Why your cheap-as-chips residential ADSL Broadband account is broken, and why I don’t care”

I could go on with all the complaints that I’ve heard over the last 24 hours, and all the stupid reasoning behind those complaints. But I won’t. I’ll try and be helpfully informative.

So we’ll start with the facts:

  • Seacom is one of the Submarine fiber cables that connect South Africa to Europe.
  • There are other ways out of South Africa to Europe, that do not rely on Seacom.
  • Residential ADSL users are quite far down the list of priorities for most ISP’s.
  • Business users on leased lines account for significantly more income than ADSL users.
  • You get what you pay for.

Your choice of ISP should take all of these facts into account:

  • Does your ISP have multiple international circuits?
  • Are these circuits physically diverse (ie: not the same cable).
  • Are you actually paying for a service that will make use of the backup circuits in the event of a failure?

Chances are, unless you have a leased line service, and you pay something in the region of R20000 a month for it, you will be affected by the Seacom problems.

It would be incredibly naive of any ISP to expect that a single upstream provider will be up 100% of the time. Seacom do not promise a 100% uptime, so how can you expect that level of service if you rely solely on them?

The solution for the ISPs? Use one of those other forms of international connectivity. Such as the SAT3-SAFE cable. Sure, thats expensive, so only use that for your “premium” customers. Like those guys paying R20000+ a month for their leased lines. They’ll get what they pay for.

And that there, is the difference between the R900 you pay a month for 4mbit ADSL, and R20000 per month for 4mbit leased line.

You get what you pay for.

mini-guide: Basic OpenVPN Server

This post is especially for Rommel. He saw my last mini-guides on OpenVPN on RouterOS, and wanted to know how to set up an OpenVPN Server on Linux that operates the same as the OpenVPN Server in RouterOS.

So, this one will be short and simple, as there are a thousand different ways to do an OpenVPN Server on linux, but this way will make it work the same way its configured in my mini-guide.

Continue reading mini-guide: Basic OpenVPN Server