[isp-dns] Linux based ISP class DNS

[Milind Nanal <milindyn@rolta.com>]

Hi, 


I am working on prime ISP company. Current we are running our DNS service
with Bind 8 series. 

I am  looking for upgrading DNS service. Any suggestion on best linux based
open source DNS service. Or I should go for BIND 9? What about djbDNS or
Tiny DNS with DNScache? 
Any issues in migration from Bind 8 to any other best DNS service.

Quick response is highly appreciated.

Regards,

Milind