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Webmail and reverse lookup

Discussion in 'E-mail Discussions' started by rsutc, Dec 29, 2017.

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  1. rsutc

    rsutc Well-Known Member

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    Recently, to foil a spammer who was spoofing a return address on our server, I enabled reverse PTR lookup. However, this killed Webmail. A user could sent a message through the box using a mail client, but any attempt by a user to send one through Webmail was forbidden by administrative policy. A search of the exit logs showed that the attempt to send was being foiled by a reverse lookup failure on the sender by our own box! Yet, I had disabled spam checks on outgoing mail. So...what is the problem here and how do I address it. I don't want to leave reverse lookup disabled. And yet..it cannot truly function for all domains because many share a single IP.
     
  2. rsutc

    rsutc Well-Known Member

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    That should be exim logs. Mumble mumble spell checker.
     
  3. cPanelMichael

    cPanelMichael Forums Analyst
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    Hello,

    Could you confirm the specific option you enabled and how you enabled it?

    Thank you.
     
  4. rsutc

    rsutc Well-Known Member

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    In the section of the advanced EXIM config:
    custom_begin_check_message_pre

    I put:

    require verify = reverse_host_lookup

    message = Your mail server IP address ($sender_host_address) has no reverse DNS PTR

    This has worked in the past, but this time Webmail could not work.

    Rick
     
  5. cPanelMichael

    cPanelMichael Forums Analyst
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