scaling of DNS & mail servers

[Thomas Duterme]

Hi everyone,

Just a quick question. I have a series of small qmail servers (6 of 'em so far) and our organzation is scaling mail linearly for now.  (I don't see us getting above 6 any time soon though...)

My question: each of these mail servers is a pretty low end box (PIII- 800, 256 K RAM, pizza box server).  In the past, I had them all pointing to my slave server (a nicer Dell 4300 512 RAM 600 CPU server).  But these boxes are now being used by marketing for promotions to our user base (a series of in-house lists)

So each of those mail servers runs into periods of high usage..therefore highlookups.  I read earlier on another thread someone recommending a very simple and clean method to scale DNS with mail.  Each mail server gets its own caching dns server.

I'm planning on implementing this and locking the box down properly (no queries from anyone but itself), but I wanted to hear what others had to think about this type of scaling.  Are there any other ideas on how to scale mail and dns properly?


TIA,
-Thomas