kiwi(_at_)oav(_dot_)net wrote:
This my policy on my mailservers for more than 2 years.
It does not reject (egg 550), but just send a tempfail return (450)
when DNS send a temp fail (for exemple main DNS server of PTR is not
reachable), also, my servers checks that the hostname given on the PTR
exist also on zone file with same A.
Eg :
1.2.3.4 has PTR mail.foo.com, then mailserver will check that
mail.foo.com as 1.2.3.4 as IP.
This kind of rule elimate 80% of spam. Other servers are just half
configured systems, so colateral damages are not too mutch big.
/Xavier
Except for webhosting companies who have 1000's of domains on a single
IP address. Right?