[CentOS] Bind DNS service

Hi everybody,

I have a request from a client that is an planning on a small ISP
business. I am looking into a DNS {bind based} solution.
 Are there any hints or tips concerning hardware requirements?
Is there any kind of tool to perform the sizing?
Should I have different machines for caching ?
Should i compile bind myself for xtra performance. There are going to
be some 400K dsl customers and some 50-70K virtual hostings
I know that most dns trafic is generated by MX lookups.

Any hints are greatly appreciated.

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Zaharioudakis Nikos
mob: +30 6947204063
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