mails rejects due to DNS check and protocol checks under MTA

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rishi.saini34
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Joined: Thu May 19, 2022 10:38 am

mails rejects due to DNS check and protocol checks under MTA

Post by rishi.saini34 »

Hi,

I have setup my own zimbra and it is working fine.

But I am not getting mails from some domains that are not properly configured and my zimbra is rejecting the mails.

These domains are important domains and we need mails from these domains.

some DNS checks are

reject_unknown_client_hostname
reject_unknown_reverse_client_hostname
reject_unknown_helo_hostname


I do not want to uncheck these options as I do not want that my server came in any blacklist due to spamming.


How I can allow only specific domains to bypass these options so that I can receive mails.

Due to enable these options mails are getting rejecting.

Kindly help.


Regards,
Rishi Saini
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L. Mark Stone
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Re: mails rejects due to DNS check and protocol checks under MTA

Post by L. Mark Stone »

With those settings you will block an awful lot of legitimate inbound email.

Suggest you use only reject_non_fqdn_sender in the Protocol Checks section of the Admin Console > Configure > Global Settings > MTA and reject_unknown_sender_domain in the DNS checks section.

If you are using commercial blocklist providers, e.g. Spamhaus and invaluement like I do, you can add their entries as appropriate in the four RBL sections in the bottom of the DNS checks section.

Hope that helps,
Mark
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L. Mark Stone
Mission Critical Email - Zimbra VAR/BSP/Training Partner https://www.missioncriticalemail.com/
AWS Certified Solutions Architect-Associate
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