Bypassing BT's DNS Service

I suffered from BTs failure yesterday which knocked out many sites though thankfully it didn't seem to affect nonfunctionalarchitect.com - phew! What a relief huh?

Anyway, BT has now apologised for the incident and is investigating root-cause. Well, feeling lost and detached from reality without full and proper access to the net (internet access should be a human right) I naturally did my own investigating which included the obligatory reboots to no avail (my Mac, wife's PC, home-hub) - and you know they'll make you redo these steps if you have to call support...

Some sites could be pinged, some couldn't (could not resolve host) which points at a DNS issue. Bypassing BTs DNS isn't that easy though as they have a transparent DNS service in place which means you can't just add Googles free DNS servers to your list ( and if you're interested). Doing this  in my case simply resulted in an error message saying that BT's Parental Controls were on a prevented me using another DNS service. Turning parental controls off stopped the error message but didn't help me resolve names because the transparent DNS service remains intercepting any requests.

I could only think of two methods to bypass BT's DNS service:

1. Use a VPN.

This will still rely on BT's network but prevents them from intercepting anything since it's all secure in a warm and cosy encrypted VPN tunnel. The only problem here is finding a VPN end-point to connect to first - I have one, but its to allow me remote access to my house which in turns relies on BT. Doh!

2. Use TOR (The Onion Ring) and Privoxy.

This prevents DNS lookups from the browser (hence use of Privoxy) and all requests are sent over the TOR network and may surface anywhere in the world (preferably somewhere not using BT's DNS service though I have little control over this). It's not the fastest solution but it works. Fortunately I had an old VM with TOR and Privoxy installed and configured so with a few tweaks to this (listen on (all addresses) rather than (localhost only)) I could configure all the machines in the house to use this VM as a proxy service and bingo! We were back online and didn't have to risk talking to each other anymore - phew!

TOR is awesome and useful for accessing sites which may be blocked by your service provider, your government or for some other legal issue (such as why the really cool but generally inaccessible BBC Future site is blocked from fee paying British residents). It's also useful if you want to test stuff from somewhere else in the world over what feels like a wet piece of string for a network.

Resiliency worries needs to be considered before you have failure. In this instance you need to have a VM (or physical machine) pre-configured and ready for such an emergency (and don't call 999, they won't be able to help... ). Smug mode on!

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