Getting Hammered Because of DNSimple?

Poor DNSimple is, as of writing, undergoing a massive denial of service attack. I have a number of domains with them and, up until now, I’ve been very happy with them. Now it isn’t fair of me to blame them for my misfortune as I should have put in place a redundant DNS server. I’ve never seen a DNS system go belly up in this fashion before. I also keep the TTL on my DNS records pretty low to mitigate any failures on my hosting provider. This means that when the DNS system fails people’s caches are emptied very quickly.

DNS has been up and down all day but it is so bad now that something had to be done. Obviously I need to have some redundancy anyway so I set up an account on easyDNS. I chose them because their logo contains a lightning bolt which is yellow and yellow rhymes with mellow and that reminds me of my co-worker, Lyndsay, who is super calm about everything and never gets upset. It probably doesn’t matter much which DNS provider you use so long as it isn’t Big Bob’s Discount DNS.

I set up a new account in there and put in the same DNS information I’d managed to retrieve from DNSimple during one of its brief periods of being up. I had the information written down too so either way it wouldn’t be too serious to recreate it. It does suggest, however, that there is something else you need to backup.

In EasyDNS I set up a new domain

in the DNS section I set up the same records as I had in my DNSimple account.Finally I jumped over to my registrar and entered two of the EasyDNS server as the DNS servers for my domain and left two DNSimple servers. This is not the ideal way of setting up multiple DNS server. However from what I can tell DNSimple doesn’t support zone transfers or secondary DNS so the round robin approach is as good as I’m going to get.

With the new records in place and the registrar changed over everything started working much better. So now I have redundant DNS servers for about $20/year. Great deal.

 

The Craziest Technology You’ll Read about today

Sorry for the alarmist title, I swear that I’m not attempting to bait your clicks… well not much.  This is awesome. I was talking with a couple of guys who work at a directional drilling company. They drill conventional oil recovery wells in order to extract a substance made from bits of old plants and animals. Drilling is way more complicated at that scale than the drilling a hole in you wall scale. The holes are thousands of feet down and, in many cases, in a weird crooked line (hence the directional drilling part). You have to do that because it may be more efficient to drill through a certain substrate at 500 feet and then move over a bit at 1000 feet. The level of accuracy these guys can do now is out of this world.

I was really intrigued about how they got information back from the drill head. There are tons of interesting readings you can gather from the head but the problem is that it is way under ground. Getting that data back is difficult. I have trouble getting wi-fi in my bedroom when the router is in the living room so clearly wi-fi is out as a technology.

Running a cable down there is also difficult. Unlike the putting a picture on the wall sort of drill these drills have lubricants and rock cuttings to deal with. Mud is pumped down the inside of the shaft and then recovered out the sides.

Thanks to the Energy Institute for this picture – http://www.energyinst.org/home

This means that any cable path is already full of highly abrasive mud. The guys told me that does work but it is flaky and you end up spending a lot of time replacing cables and also signal boosters every 200 or 300 feet.

Another way is to use low frequency radio waves which are a bit better than wi-fi at getting through rock. However there are some rocks through which it just doesn’t work to send radio waves.

The final method, and the coolest, is to use mud pulses. The mud being pumped down the well is at huge pressure (as you would expect from pumping mud). On the drill head there is a valve which can be opened and closed by the sensors on the drill head. When closed the pressure in the mud pumps increases and when opened it decreases. They literally send pulse waves through the mud they’re pumping into the well and measure them at the surface. It is outrageously low bandwidth but that it actually works at all is amazing to me. It is effectively a digital signal in mud. What a cool application of technology!

It gets better, though. If you have a valve with various open and closed settings you can vary the pressure to create a waveform varying both amplitude and frequency.

At shallow depths you can get as much as 40bit/s through mud pulsing although at deeper depths that drops off significantly to perhaps 1.5bit/s at 12 000m. 40 bit/s means that we’re running at 40Hz which is fricking huge for a mechanical valve under that much pressure to open and close.

I would not have invented this.