Tricky DNS Question - Advanced

[Marc Perkel <ma...@perkel.com>]

I have another tricky DNS question. I'm scream testing my new dnsbl 
server and I'm going to open it up for others to use soon. Just working 
out the final details.

So - here's my tricky question. I have 2 DNS servers. Server A runs 
MyDNS - a MySQL driven server. It's the one that does the work behind 
the scenes. It has no caching and should be considered to be slow.

Server B is a regular DNS server set up for caching and running BIND. 
It's the one that will be the public face for the blacklist providing 
caching for Server A so as not to load down Server A.

So what I want is that Server B secretly knows where Server A is so that 
any request of dnsbl.junkemailfilter.com goes to Server B and Server B 
passes the request on to Server A and caches it reducing the load on 
Server A and keeling it hidden from the world.

So - how do I do that? What do I put in named.conf to tell it to route 
certain requests to a Server A?

Thanks in advance.

Re: Tricky DNS Question - Advanced

[Sanford Whiteman <sw...@cypressintegrated.com>]

> Server  B  is  a  regular  DNS server set up for caching and running
> BIND.  It's  the  one that will be the public face for the blacklist
> providing caching for Server A so as not to load down Server A.

Make  B  -- and, believe me if you are operating a public blacklist, C
and  D  and E as well :) -- a secondary to primary A, with A thus your
unpublished "stealth primary" for the zone.

B,  C,  D, E are the published authoritative NSs for the zone, while A
is  "secretly,"  as  you put it, the truly authoritative source of the
zone  data  served  to  the world by B, C, D, E. This is a good way to
take  advantage  of  the  flexibility/updatability  of  RDBMS backends
without  worrying  about  the  RDBMS-backed  server  seeing any direct
traffic.

--Sandy