Imail doesn't do that yet and simply closes the connection.
ok, that's not tarpitting.
If an Imail server is getting bombed with large number of abuse msgs each
with many RCPT TO: per SMPT session, then Imail brutally disconnecting the
tcp session will help that specific problem.
When I first started IMGate work about 6 years ago, spammers were trying to
go fast and force feed MXs using multiple recipients per SMTP session, but
I haven't seen any of that tactic in last 3 or 4 years.
But that may be because IMGate has more aggressive setting to stop that
type of abuse. IMGate will also brutally disconnect an SMTP session, but
after postfix returns a max of smtp_hard_error_limit ("shel") of 5xx
rejects in one session, eg, 3 each of 5xx rejects in one SMTP session,
postfix hangs up.
Since the spammers RCPT TO: are usually bogus recipients (dictionary), the
most common shel disconnect is bad recipients. ie, IMGate never sees 20+ or
30+ recipients like Imail does because after 3 bad recips, IMGate hangs up.
Len
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