Issue Incomming Mails from a specific sender Stuck in MailQueue

[AlexandervH]

Since a couple of Days I have an issue in one of our Plesk installations:
"
OS
Debian 9.13
Product
Plesk Obsidian
Version 18.0.42 Update #1, last updated on Mar 16, 2022 06:25 AM
"
Mails from a specific Sender "GMX.de" (german E-Mail Service) land in the Mailqueue and are stuck there.
Sometimes they get bounced with the error message
" Command time limit exceeded: "/usr/lib/plesk-9.0/postfix-local" "

When watching the /var/log/maillog

this happens when they come in:

Mar 29 11:36:59 untld psa-pc-remote[4891]: 656656C32E7: py-limit-out: stderr: INFO:__main__:No SMTP AUTH and not running in sendmail context (incoming or unrestricted outgoing mail). SKIP message. Mar 29 11:36:59 untld psa-pc-remote[4891]: 656656C32E7: py-limit-out: stderr: SKIP Mar 29 11:36:59 untld psa-pc-remote[4891]: 656656C32E7: check-quota: stderr: SKIP Mar 29 11:36:59 untld psa-pc-remote[4891]: 656656C32E7: spf: stderr: PASS Mar 29 11:36:59 untld postfix/qmgr[5016]: 656656C32E7: from=<example@gmx.de>, size=4442, nrcpt=1 (queue active) Mar 29 11:36:59 untld postfix-local[6497]: 656656C32E7: from=<example@gmx.de>, to=<example@example.com>, dirname=/var/qmail/mailnames Mar 29 11:36:59 untld postfix/smtpd[6456]: disconnect from mout.gmx.net[212.227.15.15] ehlo=2 starttls=1 mail=1 rcpt=1 data=1 quit=1 commands=7 Mar 29 11:36:59 untld postfix-local[6497]: 656656C32E7: dk_check: stderr: PASS

I have run the automatic repair for plesk mailserver that didn't help either.

Anyone know what the issue could be?

 

[IgorG]

Sometimes they get bounced with the error message
" Command time limit exceeded: "/usr/lib/plesk-9.0/postfix-local" "

Mail delivery fails because DNS requests in Plesk's DMARC mail handler block indefinitely.
After 1000 seconds of waiting (by default), Postfix pipe daemon gives up and shuts down the postfix-local delivery process, which is responsible for delivery to Plesk's mailboxes.
If temporarily disabling DMARC checks help, you must fix DNS records/settings.

 

[AlexandervH]

Mail delivery fails because DNS requests in Plesk's DMARC mail handler block indefinitely.
After 1000 seconds of waiting (by default), Postfix pipe daemon gives up and shuts down the postfix-local delivery process, which is responsible for delivery to Plesk's mailboxes.
If temporarily disabling DMARC checks help, you must fix DNS records/settings.

Ok temporarily disabling Dmarc helped. But how do I fix my DNS settings for this? And why is only one specific sender affected?

 

[eddvond]

I am having the exact same problem.Disabling DMARC helped, but this is not an option in my case.