Martijn de Munnik wrote:
Hi,
On Jul 13, 2009, at 7:57 PM, Noel Jones wrote:
Martijn de Munnik wrote:
smtpd_recipient_limit = 25
only if you have 25 or fewer users.
I thought this means a user can send an e-mail to 25 users max at once?
After $smtpd_recipient_limit + 1 RCPT TO commands, your server
will respond "too many recipients" to subsequent RCPT TO
commands. This is a temporary error; the first 25 recipients
are accepted & delivered. The sending client is free to try
additional recipients later.
If the other end is an MTA, it will likely try the remaining
recipients "later", based on its retry schedule. This can
cause significant delays to legit multi-recipient mail, and
can increase load on your system.
If the other end is an end-user program, it may give the user
some cryptic message. This can annoy legit users trying to
send to a list of people.
If the other end is a spammer, you've already accepted 25
recipients, and they're free to reconnect and try more.
This is not an effective anti-spam control if that's what
you're trying to use it for. You'll probably have better
results with a fairly low smtpd_hard_error_limit and working
recipient validation (clients are disconnected after
$smtpd_hard_error_limit bad recipients).
-- Noel Jones
