On Tue, 6 Nov 2007, Arthur Sherman wrote:

> A client asked me to build for him a mail solution, capable of sending up to
> 1 milllion emails a day, while each email doesn't exceed 50KB in size.

1 million a day really isn't such a tall order.  Since from other messages 
in the thread, it sounds like you've admitted this will be UCE / CAN-SPAM 
compliant spam, I suggest a 486 with 16mb RAM, and 540mb hard drive. 
Those should literally be a dime a dozen.

> How do I calculate:
> 1) how many servers

1 will do...really.  The only reasons for multiple servers would be 
redundancy (if the server goes down, the ISP cuts it off, IPs get 
listed) or load sharing if how long it takes to complete a delivery run is 
worth the additional cost.

> 2) how do I calculate the above

See above.

> 3) is there any max emails a day from IP/domain, which triggers black and
> blocklists

That depends entirely on who the recipients are and if they've asked you 
to send them the email.  1000000/day to AOL users who've really subscribed 
is no problem.  1000/day to AOL users who didn't is likely to be an issue. 
1 to the wrong spamtrap could be disastrous.

What IP space will your client be sending from?

> 4) what is your recommended software solution

Long ago, I ran a high volume large mailing list (everyone really did 
subscribe) and sendmail couldn't deal with it.  I setup zmailer on some 
POS box we had available, and it handled it.  I don't know if zmailer is 
even still maintained, but any of the modern MTAs should work.

  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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