I'm running a dovecot/postfix mail server on debian and am having some issues. Everything is working fine except all emails to @aol.com are being deferred.
The error code gave me: "The Reverse DNS lookup for your IP address is failing."
I'm running a site (I'll be calling it site.com in this post) on server A. I'm then running this mail server on server B. I have a mail.site.com A record pointing to server B in my domains DNS, as well as an MX record pointing to mail.site.com.
I've set the PTR record of my mail server to site.com and this is the dig output:
*I've substituted 188.8.131.52 for the IP of my mail server
AND 184.108.40.206 as my main server IP
dig -x 220.127.116.11 @18.104.22.168 ; <<>> DiG 9.3.6-P1-RedHat-9.3.6-20.P1.el5_8.6 <<>> -x 22.214.171.124 @126.96.36.199 ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 48367 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;188.8.131.52.in-addr.arpa. IN PTR ;; ANSWER SECTION: 184.108.40.206.in-addr.arpa. 21599 IN PTR site.com. ;; Query time: 58 msec ;; SERVER: 220.127.116.11#53(18.104.22.168) ;; WHEN: Tue Jul 22 14:30:23 2014 ;; MSG SIZE rcvd: 75
In site.com's domain DNS settings I have:
A | site.com -> 22.214.171.124 (main server ip) A | mail.site.com -> 126.96.36.199 (mail server ip) MX | mail.site.com -> mail.site.com
I don't have any SPF or TXT records. When I ping mail.site.com it correctly returns the IP of my mail server.
Why am I still getting bounce backs?
MX | mail.site.com -> mail.site.com
MX | site.com -> mail.site.com
Also, as @sebix suggested I had to confirm my HELO was set as mail.site.com (it was set to site.com) as well as confirm my PTR of my mail server was set to mail.site.com (it was set to site.com)