On Tue, Apr 14, 2015 at 10:09 AM, Pavel Odintsov <pavel.odintsov@gmail.com> wrote:
We use hexademical numbers in PTR for VPS/Servers because PTR's like "host-87.118.199.240.domain.ru" so often banned by weird antispam systems by mask \d+\.\d+\.\d+\d+ as home ISP subnets which produce bunch of spam.
Hi Pavel, Actually, the anti-spammers figure that only local (authenticated) computers and other mail servers should talk to their mail servers. The IP form of RDNS is recognized as a declaration by the service owner that the computer at that address is not intended to host Internet services including email. The hex form is viewed the same and yes, there are antispam products that look for that and a few other naming structures that imply dynamic IPs are in use. If you want to run an email server, assign it a name. Regards, Bill Herrin -- William Herrin ................ herrin@dirtside.com bill@herrin.us Owner, Dirtside Systems ......... Web: <http://www.dirtside.com/>