Sunday, December 17, 2006

DNS black holes

A long time ago, I experimented with forging domain authority on internal DNS servers as a anti-spam/anti-porn measure. It does work though I don't recommend it as a countermeasure unless you're willing to devote (I'm not kidding) a lot of time to updating the zone files. Over a one year period, I added 21K zones and still could not get ahead of the game.

I guess it would help to have an organized project to rely on. Something like Bleeding Edge's black-hole DNS project. Mix in a little policy-based routing (IP and port redirects that are invisible to users) and your troublemakers get quite frustrated. If you manage a network, I recommend looking at this.

Side note: what you use as a DNS server will determine how well you can scale the project. Windows DNS handles 21K domains poorly. Linux doesn't fare much better. (They do work but overload easily.) FreeBSD variants a bit better. The one that I recommend as a DNS server for heavy uses is BSDi (the commercial one). Wind River purchased BSDi and discontinued the product some time in 2003. It's still a very stable platform if you have the license.

Side note: Wind River has purchased and discontinued at least one other OS. They're also the parent to VxWorks, which is that annoying OS in the newer 54G's. Would it suprise you that they've also been a partner to Redhat?