Hi guys,
I have an issue, with the solution of which I have unfortunately not progressed even after intensive search on the net. Maybe you can help me.
The basic issue is that I can’t deliver mails in a certain size (where exactly the limit is, I can’t say) to mailcow, more specifically I think to Postfix.
Postfix generates a
“4.7.1 Service unavailable - try again later; from=<x@y> to=<x.y@z> proto=ESMTP helo=<[10.11.12.2]>”
to the delivering mail client (tried several software).
Here is the corresponding postfix log of one of those failing sessions (hostnames, email addresses and IP addresses have been obscured):
11/07/2023, 14:58:18 info disconnect from host.name[1.2.3.4] ehlo=1 auth=1 mail=1 rcpt=1 data=0/1 commands=⅘
11/07/2023, 14:58:18 info 78DE83421E0: milter-reject: END-OF-MESSAGE from host.name[1.2.3.4]: 4.7.1 Service unavailable - try again later; from=x@z.tld to=x.y@z.tld proto=ESMTP helo=<[10.11.12.2]>
11/07/2023, 14:58:18 warning warning: milter inet:rspamd:9900: can’t read SMFIC_BODYEOB reply packet header: Success
11/07/2023, 14:58:05 info 78DE83421E0: message-id=480f0cbe-d53f-5dff-5229-a4c1672dc9d6@neopax.net
11/07/2023, 14:58:05 info 78DE83421E0: replace: header Received: from [10.11.12.2] (host.name [1.2.3.4])??(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)?? key-exchange X25519 server-signature RSA-PSS (4096 bits))??(No client from host.name[1.2.3.4]; from=x@z.tld to=x.y@z.tld proto=ESMTP helo=<[10.11.12.2]>: Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 78DE83421E0??for x.y@z.tld; Tue, 11 Jul 2023 14:58:05 +0200 (CEST)
11/07/2023, 14:58:05 info 78DE83421E0: client=host.name[1.2.3.4], sasl_method=PLAIN, sasl_username=x@z.tld
11/07/2023, 14:58:05 info Anonymous TLS connection established from host.name[1.2.3.4] to host.of.mailserver.tld: TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)
11/07/2023, 14:58:05 info connect from host.name[1.2.3.4]
It seems to be clear that the error is correspondent with the log line
11/07/2023, 14:58:18 warning warning: milter inet:rspamd:9900: can’t read SMFIC_BODYEOB reply packet header: Success
My numerous attempts to find a real, targeted solution to the above error message have unfortunately failed so far. Maybe someone here in the large mailcow community has an idea where I could start!
The system is running mailcow 2023-05a on Ubuntu 20.04.6 LTS.
Best regards and thanks for your input!