Reverse DNS does not match SMTP Banner

[sameone]

Hello

I use mxtoolbox to test - > smtp:Test mail server SMTP (port 25)


Then I become warning: Warning - Reverse DNS does not match SMTP Banner


How to fix that ??


I read on forum, that I have to change main.cf (smtpd_banner).

Have someone did that ??


In my main.cf I found:
smtpd_banner=$myhostname ESMTP $mail_name

What I have to change?


Thanks all

[jgt]

Sounds like the name of your system, and the domain name that your external ip address resolves to, are different.
This does not in itself prevent your system from sending emails, but, there are many email servers that will not accept incoming email if the domain portion of the sending email address does not resolve to the ip address of the sending system.
If the domain name returned by your ip address does not match your mail domain name, then speak to your isp about having that set up, otherwise change the name of your mail server to match.

[sameone]

Thanks for help

my hostname: mail4
my domain: zimbra.com
mail4.zimbra.com


My ISP is (My provider have my IP and MX ..): mail.zimbra.com

zimbra.com is not really my domain


What to do ??

[jgt]

Go here Reverse DNS Lookup , enter your external ip address, and see if your domain name is returned.

[sameone]

Yes. Thats not a Problem.