I have an SMTP server running on a vultr VM. I've set up the rDNS to point to my mail domain name mail.idimitrov.dev. The DNS setup points to that machine on ipv4 and ipv6 for mail.idimitrov.dev and it points to github pages on idimitrov.dev.
When I send emails to gmail only, it tells me that there are no PTR records.
| host gmail-smtp-in.l.google.com [2a00:1450:4013:c07::1b]
| SMTP error from remote mail server after pipelined end of data:
| 550-5.7.25 [2001:19f0:6c01:2f25:399c:6832:fa7c:c123] The IP address sending this
| 550-5.7.25 message does not have a PTR record setup, or the corresponding
| 550-5.7.25 forward DNS entry does not point to the sending IP. As a policy,
| 550-5.7.25 Gmail does not accept messages from IPs with missing PTR records.
| 550-5.7.25 Please visit
| 550-5.7.25 https://support.google.com/mail/answer/81126#ip-practices for more
| 550 5.7.25 information. fl6-20020a1709072a8600b008b466a03af6si17950149ejc.3 - gsmtp
This is not the case for other mail providers.
I changed the rDNS settings to point to idimitrov.dev and tested again. Same result.
Here is the output of the dig command:
~ ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── at 08:55:53
❯ dig -x 209.250.239.243
; <<>> DiG 9.18.12 <<>> -x 209.250.239.243
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64879
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; COOKIE: 96ded523f01fcbcb0100000063f70e07b977d3b949d3c8d8 (good)
;; QUESTION SECTION:
;243.239.250.209.in-addr.arpa. IN PTR
;; ANSWER SECTION:
243.239.250.209.in-addr.arpa. 3321 IN PTR idimitrov.dev.
;; Query time: 0 msec
;; SERVER: 192.168.0.1#53(192.168.0.1) (UDP)
;; WHEN: Thu Feb 23 08:56:07 EET 2023
;; MSG SIZE rcvd: 112
~ ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── at 08:56:07
❯ dig -x 2001:19f0:6c01:2f25:5400:04ff:fe48:12ba
; <<>> DiG 9.18.12 <<>> -x 2001:19f0:6c01:2f25:5400:04ff:fe48:12ba
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 32491
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; COOKIE: 82062aa836133bb70100000063f70e0a54a88c9478150aaa (good)
;; QUESTION SECTION:
;a.b.2.1.8.4.e.f.f.f.4.0.0.0.4.5.5.2.f.2.1.0.c.6.0.f.9.1.1.0.0.2.ip6.arpa. IN PTR
;; ANSWER SECTION:
a.b.2.1.8.4.e.f.f.f.4.0.0.0.4.5.5.2.f.2.1.0.c.6.0.f.9.1.1.0.0.2.ip6.arpa. 3445 IN PTR idimitrov.dev.
;; Query time: 0 msec
;; SERVER: 192.168.0.1#53(192.168.0.1) (UDP)
;; WHEN: Thu Feb 23 08:56:10 EET 2023
;; MSG SIZE rcvd: 156
It shows that I have rDNS setup for both ipv4 and ipv6.
Why does google say otherwise?
