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Diffstat (limited to 'mail/milter-sender/DESCR')
| -rw-r--r-- | mail/milter-sender/DESCR | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/mail/milter-sender/DESCR b/mail/milter-sender/DESCR index e69de29bb2d..823222b42d9 100644 --- a/mail/milter-sender/DESCR +++ b/mail/milter-sender/DESCR @@ -0,0 +1,21 @@ +Spam is the black plague of the Internet world and this Sendmail milter +attempts to address a small subset of the problem by verifying that the +sender's email address is in good standing by performing an SMTP callback +to the MX server responsible for the sender's domain. This milter is not +intended to be a complete solution to spam and so it should be used in +conjunction with other tools such as DNS blacklists and content filters. + +To be in good standing, the MX server of the sender must be reachable and +willing to accept email for the sender from the Delivery Status +Notification (DSN) address, which is the null address <> used for error +reporting. This particular requirement is similar to using the +RFC-Ignornant DSN Blacklist. + +During the callback, any failure in establishing an SMTP connection such +as no DNS entry or the primary MX server is unreachable, or during the +SMTP dialogue such as not accepting the DSN, user unknown, or mail box is +full, etc. will result in the incoming mail in question being rejected. +In the case of a temporary error during the SMTP dialogue with the +sender's MX server, milter-sender will reject the current message with +a temporary error code, which the sender is then free to retry again +later. DNS lookup and connection problems are treated as temporary errors. |