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[edit] Anycast DNS

• • NOTE 172.16.1.1 is dead - replace with 172.16.15.1 as indicated below**

[edit] For the Users

The DNS server will automatically be queried based on its physical location, using the shortest possible route between you and the DNS server.

Simply change your DNS Primary address to

 172.16.250.250

[edit] For the Admins

If anyone's interested in how we did it... here's the basics. You must be participating in the OSPF backbone area, so this wont be of much use to your average client node.

1. Add a Bridge interface (call it AnyCastDNS0).

2. Add an IP of 172.16.250.250/32 to the Bridge interface.

3. In IP > DNS Click settings

3.1. Set the Primary DNS Server to 172.16.1.1 / 172.16.15.1 is now preferred

3.2. Set the Secondary DNS Server to 172.16.2.130

3.3. Tick the Allow Remote Requests tick box

3.4. Click OK

4. Test

   If you' re connected to the Router, run a traceroute to 172.16.250.250
   It should be 1 hop away.
   Disable the interface, and traceroute again.
   It will go to the next nearest AnyCast DNS Server on the network.
   Re-enable the interface, and you're done!
 

Read more here: Anycast Anycast