[Pdns-users] tracking servers through database backend?

[bert hubert]

On Thu, May 10, 2007 at 02:22:42PM +1000, Amos Shapira wrote:
> 1. A Geo backend which will pick a CNAME record based on the IP from which
> the query came.
> 2. A database backend (MySQL/PostgresSQL) which will resolve the name that
> the CNAME points to into an IP address.
> 
> I wonder if that I wrote until here makes sense.

Very much so!

> Now the twist is that I was thinking of having a specialised program which
> probes all the available servers, checks that they are still alive and well,
> and updates the records of the database back-end whenever a server's
> availablity changes.

This is one easy way of doing things, and it would work fine.

> Is this a possible plan?  How do others setup such networks?
> e.g. I read the Wikipedia uses PowerDNS with GeoIP to forward users to
> nearer servers, but does it also check whether the node or cluster it
> forwards the user to is available at all?

There are no special checks for the Wikipedia. Some other PowerDNS users
have used a special 'pipe' backend to do realtime checks of server
availability, but changing the database on server availability changes works
as well.

Good luck!

-- 
http://www.PowerDNS.com      Open source, database driven DNS Software 
http://netherlabs.nl              Open and Closed source services