The Community Forums

Interact with an entire community of cPanel & WHM users!
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Reverse DNS does not match SMTP Banner

Discussion in 'E-mail Discussions' started by rogerw, Mar 16, 2016.

  1. rogerw

    rogerw Member

    Joined:
    Feb 21, 2012
    Messages:
    9
    Likes Received:
    0
    Trophy Points:
    1
    cPanel Access Level:
    Website Owner
    Thanks... I've been running into the same issue. The resource being linked to does not resolve the issue, it discusses sending form cPanel accounts each with dedicated IP addresses, that's not quite what we need.

    We need help with a server for example: box1.domain.com <==> 123.456.789 (with appropriate PTR created) - But... When using test tools (like mxtoolbox.com) we get the "SMTP Check Banner" error that says "Reverse DNS does not match SMTP Banner".

    What this means is when a cPanel server is set up, for some reason, an incorrect banner is created (even though there's a PTR and A record for "box.domain.com").

    Any help would be immensely appreciated! :)
    Thanks!
     
  2. cPanelMichael

    cPanelMichael Forums Analyst
    Staff Member

    Joined:
    Apr 11, 2011
    Messages:
    32,645
    Likes Received:
    855
    Trophy Points:
    113
    cPanel Access Level:
    Root Administrator
    Hello :)

    Could you verify if the issue persists when temporarily disabling the "Introduce a delay into the SMTP transaction for unknown hosts and messages detected as spam" option in "WHM >> Service Configuration >> Exim Configuration Manager >> Basic Editor"? I've seen reports that this option prevents third-party utilities such as MXToolBox from completing a check of the RDNS entry.

    Thank you.
     
    linux4me2 and Suleiman Boutzamat like this.
  3. rogerw

    rogerw Member

    Joined:
    Feb 21, 2012
    Messages:
    9
    Likes Received:
    0
    Trophy Points:
    1
    cPanel Access Level:
    Website Owner
    Yes! That works! Also found that "Only-verify-recipient" - Click "Edit" and add (to allow mxtoolbox.com testing): pws3.mxtoolbox.com (but leaving "Introduce a delay into the SMTP transaction for unknown hosts and messages detected as spam" works as well. That is providing the person "trusts" mxtoolbox.com.

    Thanks cPanelMichael - Muchly appreciated! :)
     
  4. cPanelMichael

    cPanelMichael Forums Analyst
    Staff Member

    Joined:
    Apr 11, 2011
    Messages:
    32,645
    Likes Received:
    855
    Trophy Points:
    113
    cPanel Access Level:
    Root Administrator
  5. i-Strategi

    i-Strategi Member

    Joined:
    Mar 14, 2016
    Messages:
    5
    Likes Received:
    0
    Trophy Points:
    1
    Location:
    Denmark
    cPanel Access Level:
    DataCenter Provider
    This saved my life.
     
  6. luiz878

    luiz878 Registered

    Joined:
    Feb 14, 2013
    Messages:
    2
    Likes Received:
    0
    Trophy Points:
    1
    cPanel Access Level:
    Root Administrator
    Michael,

    Taking advantage of this your post I've disabled this message you mentioned above and now resolved part of my issue, but I still have this 3 errors below showing in Mxtoolbox from my IP 107.173.183.51

    SMTP Reverse DNS Mismatch - Reverse DNS does not contain the hostname
    SMTP Banner Check - Reverse DNS does not match SMTP Banner
    SMTP Transaction Time - 5.720 seconds - Warning on Transaction Time

    Can you give me a orientation how to fix it?

    Best Regards

    Luiz Osorio
     
  7. cPanelMichael

    cPanelMichael Forums Analyst
    Staff Member

    Joined:
    Apr 11, 2011
    Messages:
    32,645
    Likes Received:
    855
    Trophy Points:
    113
    cPanel Access Level:
    Root Administrator
Loading...

Share This Page