Why was this email delivered without greylisting?

Discussion in 'Installation/Configuration' started by snowweb, Aug 17, 2020.

  1. snowweb

    snowweb Member

    The email in the following log was sent by me via gmail at 19:07hrs and the very first delivery attempt succeeded at 19:08hrs.
    How is this, since I have postgrey enabled and the target mailbox is set on "Normal" spam protection policy? The gmail account has never sent email to this server before, so it is completely unknown.

    I haven't added anything in any whitelist. I'm confused. This should have been delayed right?
  2. Th0m

    Th0m ISPConfig Developer Staff Member ISPConfig Developer

    When enabling greylisting, there is a check if the sending server is known, not to email address. So probably this google server has sent you email before.

    Does greylisting work for other emails?
  3. snowweb

    snowweb Member

    The server only has one email account currently, created last Friday. I have sent from two other domains previously to this mailbox and both were greylisted and were only accepted after I made the following change on the server:
    After doing that, those emails I sent from the two external domains were then accepted, so I thought all was well.
    However, I then find the gmail somehow slides through. Definitely no other email has been received on the server from Gmail.
    Could it be that the fix I did above is the problem?
  4. Jesse Norell

    Jesse Norell Well-Known Member Staff Member Howtoforge Staff

    That would be the reason the mail was not grey listed.
  5. Th0m

    Th0m ISPConfig Developer Staff Member ISPConfig Developer

    Lol, I didn't take a look at the headers. That would indeed be the problem :)
  6. snowweb

    snowweb Member

    Hi Thorn, as you can see below there is nothing in any whitelist (I didn't remove anything).

    upload_2020-8-18_9-0-18.png upload_2020-8-18_9-3-28.png
    Not sure if there is additional hidden whitelist maintained by postgrey? Even so, this is a brand new server. It has only ever received 3 emails in it's entire life. The email address which the logs claim was whitelisted could not possibly have been existing already in any whitelist since that gmail account hadn't sent any other email to anyone since the server was built.
    If gmail is whitelisted (in a hidden whitelist), how did that happen and where can I remove the whitelist entry? I can't see it in any of the whitelists I know of.
    You asked whether I have tried "turning it off and on again?". Do you mean "disabling and re-enabling" Postgrey?
  7. till

    till Super Moderator Staff Member ISPConfig Developer

    You ix up whitelists here, the postgrey whitelist is not connected to ISPConfig, its a file in /etc/postgrey. And if I remember correctly, postgrey is whitelisting some large email providers by default that do not support greylisting or in other words, if you would enable greylisting, then the emails would either not arrive or would have huge delays as the provider does not retry the delivery in a shorter amount of time. So generally spoken, it is recommended to not mess with this and removing gmail from the whitelist will not give you any benefits except of maybe some lost emails.
  8. snowweb

    snowweb Member

    Hi Till,
    Many thanks for your assistance. You were quite right, /etc/postgrey/whitelisting_clients contained I think around a hundred providers and I was able to confirm that this was the problem with the testing. It's all good now.
    Appreciate your help :)
    Th0m likes this.
  9. Th0m

    Th0m ISPConfig Developer Staff Member ISPConfig Developer

    That's just my signature, a quote from the IT crowd which is often the first thing to try when something is broken ;)
    snowweb and elmacus like this.
  10. snowweb

    snowweb Member

    Haha! Actually, I did "reboot" but just didn't want to admit it!
    Th0m likes this.

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