Thoughts on a large-scale DNS server...

[Jon Simola]

On 6/28/05, Matthew D. Fuller <fullermd at over-yonder.net> wrote:

> CPU?  Sure.  Memory?  Quite probably.  Even if you assume each zone
> will eat 64k of memory (which I think it a terribly high guess; at
> least double what you'd really expect), 11,000 zones will burn less
> than 700 meg.  I'd probably be tempted to double the memory, just
> because memory is cheap&easy, but I doubt you'll be hitting a wall on
> it.

I'd recommend, if you have the time, to look into djbdns's tinydns. It
uses a compiled DB file for speed and size. On the djbdns mailing
lists there has been a few posts from some large-scale admins who use
it to serve 500,000 zones, using about 300MB of ram on some mid-grade
P4 machines handling 500 queries a second. One of the main reasons I
remember they had switched was BIND's startup delay.

Myself, I've only got 500 zones and it only uses 800K of memory. It's
certainly nothing like BIND, here's all the raw source for a single
domain, 2 nameservers, a webserver and an MX.
(The . record generates an SOA, an NS at a.ns.mecha.ca, and an A for
a.ns.mecha.ca -> 207.194.110.192. The & generates the second NS and A
record, @ is the MX a.mx.mecha.ca and the A for a.mx.mecha.ca ->
207.194.110.192, and the + is an A)

.mecha.ca:207.194.110.192:a
&mecha.ca:207.194.110.196:b
@mecha.ca:207.194.110.192:a
+www.mecha.ca:207.194.110.192

-- 
Jon Simola
Systems Administrator
ABC Communications