Reverse DNS does not match SMTP Banner

[oomaro]

Usually telnet is not installed by default, in that case you can install it:
yum -y install telnet

it is ok I am an expert in Linux.

 

[oomaro]

also I got this now

 

[mtindor]

If your server IP address is the 135.181.xxx.yyy address, it reverse resolves to static.yyy.xxx.181.135.clients.your-server.de

Is the hostname of your server (as configured in WHM) really static.yyy.xxx.181.135.clients.your-server.de ? I can't tell because when I try to connect to the mailserver on 135.181.xxx.yyy it is refusing mail from my country lol. Nice one.

Anyway, if your hostname as configured in WHM is something other than static.yyy.xxx.181.135.clients.your-server.de, then your reverse DNS is not set up properly.

 

[ITHKBO]

Isn't this message a well known false positive with mxtoolbox due to the way EXIM SMTP transaction delay works?

Tutorial - MXToolbox SMTP Failures (false positives)

Overview MXToolBox is a third-party service that provides many basic SMTP server tests. The test results sometimes include misleading results for cPanel & WHM servers. Test Results The SMTP email server test may return errors on the SMTP Banner...

forums.cpanel.net

Please keep in mind that the mentioned IP ranges in the post are outdated if you want to add them use the once provided by mxtoolbox itself

MxToolBox Support Services

mxtoolbox.com

 

[cPRex]

Yes, part of this issue is due to the SMTP delay.