> Is there a good rule-of-thumb for what to set the MaxRecipients pamarater
> to in sendmail?
RFC821 says that SMTP servers have to handle 100 recipients, but the
usual number seems to be 20.
> And the meta question: what happens to the sending server if the limit
> is exceeded... are the servers clever enough to requeue the message
Not that I've seen. On the other hand, I don't know of any MTA that sends
more than 20 addresses per transfer, and the only ones who can't handle that
are deliberately broken as a badly implemented spam filter.
Incidentally, if you have reasonable bandwidth, your overall throughput will
probably be better if you send one receipient per message as qmail does, even
though the total bytes transferred is more, due to increased overlap and less
waiting for round trip handshakes.
John Levine, firstname.lastname@example.org, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be, http://iecc.com/johnl, Sewer Commissioner
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