New email server problems


Comparing my new server IP ranges against my old server IP ranges.

$ host 14.28.185.106.list.dnswl.org
14.28.185.106.list.dnswl.org has address 127.0.6.2
$ host 54.98.104.172.list.dnswl.org
54.98.104.172.list.dnswl.org has address 127.0.6.0
IP ASN rbl abuse hostname magnitude score first/last seen
106.185.28.14 2516 0 0 tk.zumbi.com.ar 0.00 med 2014-07-18/2018-04-19
172.104.98.54 63949 0 0 mail.zumbi.com.ar 1.76 none 2018-04-25/2018-05-09
2400:8900::f03c:91ff:fe73:ff2f 2516 0 0 tk.zumbi.com.ar 0.00 med 2017-04-11/2018-04-07
2400:8902::f03c:91ff:fea6:496c 63949 0 0 mail.zumbi.com.ar 0.00 none 2018-04-25/2018-04-25

This was as May 2018, after a month with new email server. This shows that new IPs are problematic for email delivery.

2 months after, in July, I had to ask for new IP6 ranges for my email server because spamhaus would list and unlist my new server's IP6 range. In the meantime my new IP4 is more trusted by dnswl.org

$ host 54.98.104.172.list.dnswl.org
54.98.104.172.list.dnswl.org has address 127.0.6.2
IP ASN rbl abuse hostname magnitude score first/last seen
2400:8902::f03c:91ff:fea6:496c 63949 10 0 mail.zumbi.com.ar 0.00 none 2018-04-25/2018-04-25


2 months and 2 weeks after, this is how my IP ranges look like in dnswl.org

IP ASN rbl abuse hostname magnitude score first/last seen
172.104.98.54 63949 0 0 mail.zumbi.com.ar 2.42 med 2018-04-25/2018-07-29
2400:8902:e000::1:b001 63949 0 0 mail.zumbi.com.ar 0.00 none 2018-07-10/2018-07-10

Not bad, I'll remove smtp_address_preference = ipv4 from my /etc/postfix/main.cf soon :)