Please whitelist cPanel in your adblocker so that you’re able to see our version release promotions, thanks!

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.

Multiple Shared and Dedicated IPs

Discussion in 'E-mail Discussions' started by scits, Nov 7, 2016.

Tags:
  1. scits

    scits Registered

    Joined:
    Nov 7, 2016
    Messages:
    1
    Likes Received:
    0
    Trophy Points:
    1
    Location:
    Zurich
    cPanel Access Level:
    Root Administrator
    Hello everyone!

    I am managing a WHM/Cpanel Server which has multiple shared and dedicated IP addresses. In the EXIM configuration manager I've activated "Send mail from account’s dedicated IP address" as this is a requirement for the dedicated IP addresses. This works fine for the domains on the dedicated IPs, however it also creates an issue for the domains on the shared IPs, since the reverse DNS entry points to the server's main host name.

    Let's assume the following IP setup:
    • webserver01.domain.com - > 1.1.1.1 (server's main hostname and IP)
    • 1.2.2.2 -> shared IP (reverse DNS points to webserver01.domain.com)
    • 1.3.3.3 -> shared IP (reverse DNS points to webserver01.domain.com)
    • 1.4.4.4 -> dedicated IP for abcxyz.com (reverse DNS points to webserver01.abcxyz.com)

    If I send out an e-mail from 1.2.2.2, some recipient mail servers reject the mail, due to the fact that the reverse DNS entry points to webserver01.domain.com, which in turn points to 1.1.1.1. As stated above, sending out an e-mail from 1.4.4.4 works without any issues.

    If I see it correctly, there are two options. Either I change the configuration so that the domains on the shared IP use 1.1.1.1 for the outgoing mail, or I create an A-Record for each shared IP, e.g:

    webserver01-02.domain.com -> 1.2.2.2
    webserver01-03.domain.com -> 1.3.3.3

    Then I could point the reverse DNS entries of the shared IPs to the host names above. Would that work? Any thoughts?

    Many thanks in advance!

    Kind regards,
    RS
     
  2. cPanelMichael

    cPanelMichael Forums Analyst
    Staff Member

    Joined:
    Apr 11, 2011
    Messages:
    38,658
    Likes Received:
    1,425
    Trophy Points:
    363
    cPanel Access Level:
    Root Administrator
Loading...

Share This Page