On Mon, May 30, 2011 at 10:11 PM, Henrik Larsson dovecot-user@spambox.dkwrote:
which leads to postfix complaining:
May 30 13:28:39 mail postfix/smtpd[25014]: NOQUEUE: reject_warning: RCPT from unknown[193.210.130.67]: 450 4.7.1 Client host rejected: cannot find your reverse hostname, [193.210.130.67]; from=dovecot-bounces@dovecot.org to=hanns@hannsmattes.de proto=ESMTP helo=
If your are checking for reverse hostname and won't accept e-mails if this is not present you will reject a lot of legitimate mail.
This also stops more spam than the good mail it blocks, when people get blocked for this, they should complain to their ISP, why should we accept NON RFC compliant mail servers because the sys admin has not got around to reading dns 101?
Yes I know some ISP dont care and shrug their shoulders, I tell the people who complain to postmaster address to find an ISP who can set up their networks and cares about their users!
My employer does not pay me to sit here and update the whitelist files every 15 minutes because of some ISP who doesn't care about their users sending mail, and at my last employer a couple of years ago, we did the sums, 92% of spam stopped by rejecting no dns hosts! even here I still see it
mx-in1 ~$ cat maillog | grep -c "cannot find your hostname" 5328
mx-in2 ~$ cat maillog | grep -c "cannot find your hostname" 7041
in only 20 hours since logs rolled!!!!!!!
enjoy your spam :->