I maintain two mailcow-dockerized servers, one for my personal hobby domain (hobby.tld running Arch Linux, I’ll call this one arch.mail.server; I understand this is not supported, but I’d be surprised if that’s the root of this problem), and one for my family’s email domain (surname.tld, running Debian 12.7, debian.mail.server). I have logwatch set up to email me its output from my Arch Linux laptop (fluorine.localdomain), and postfix on it is configured to send email through my mail server at arch.mail.server using mail.hobby.tld, over the submission port (587/tcp). I have username@fluorine.localdomain and root@fluorine.localdomain set up as External sender addresses in mailcow-dockerized for hobby.tld.
Periodically messages from logwatch from fluorine.localdomain do not arrive in my inbox; I’ve seen them in the Spam/Junk mail folders in both GMail and SOGo. I’m checking both my username@surname.tld and username@hobby.tld email addresses in GMail, and the following message from logwatch on fluorine.localdomain arrived a few weeks ago, and was in the GMail Spam folder (label):
Delivered-To: username@gmail.com
Received: by redacted:5 with SMTP id fx14csp2873246ocb;
Mon, 23 Sep 2024 22:56:11 -0700 (PDT)
X-Forwarded-Encrypted: i=1; AJvYcCWGRRZPuAIJ5zqRk1+hw/EfJ3EFoeZIhaOVWc19HooN8baAnZax+1HnwB21Fw3uyGEH9eUa7fqXMe1o6mYH@gmail.com
X-Google-Smtp-Source: AGHT+IEXZa/ndomHzeSQz5ZVEFJum7v+t1OO6gItzqSXHWvCf00wiVU1bof7WUaBWEqVi+ybgRpmpELtNws=
X-Received: by redacted:19 with SMTP id 00721157ae682-6e2041312c6mr30401707b3.27.1727157371071;
Mon, 23 Sep 2024 22:56:11 -0700 (PDT)
Authentication-Results: mx.google.com;
spf=pass (google.com: found no external ips, assuming domain of
as permitted sender)
Received-SPF: pass (google.com: found no external ips, assuming domain of
as permitted sender)
Received: by redacted:0 with POP3 id 00721157ae682-6e00d35220amf7982917b3.0;
Mon, 23 Sep 2024 22:56:10 -0700 (PDT)
X-Gmail-Fetch-Info: username@hobby.tld 7 mail.hobby.tld 995 username@hobby.tld
Return-Path: <>
Delivered-To: username@hobby.tld
Received: from mail.hobby.tld ([172.22.1.253]) by fe00c26d7687 with LMTP id wKGzA+lP8mZ/DRUACxm55A (envelope-from <>) for <username@hobby.tld>; Tue, 24 Sep 2024 01:36:41 -0400
Received: by mail.hobby.tld (Postcow) id 066C97B27AC; Tue, 24 Sep 2024 01:36:41 -0400 (EDT)
Date: Tue, 24 Sep 2024 01:36:41 -0400 (EDT)
From: Mail Delivery System <MAILER-DAEMON@mail.hobby.tld>
Subject: Undelivered Mail Returned to Sender
To: username@hobby.tld
Auto-Submitted: auto-replied
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status; boundary="9A3097B27AA.1727156201/mail.hobby.tld"
Content-Transfer-Encoding: 8bit
Message-Id: <20240924053641.066C97B27AC@mail.hobby.tld>
--9A3097B27AA.1727156201/mail.hobby.tld
Content-Description: Notification
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
This is the mail system at host mail.hobby.tld.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to postmaster.
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The mail system
<username@surname.tld>: host surname.tld[redacted:1] said: 554
5.7.1 This message does not meet our delivery requirements (in reply to end
of DATA command)
--9A3097B27AA.1727156201/mail.hobby.tld
Content-Description: Delivery report
Content-Type: message/delivery-status
--9A3097B27AA.1727156201/mail.hobby.tld
Content-Description: Undelivered Message
Content-Type: message/rfc822
Content-Transfer-Encoding: 8bit
Return-Path: <username@hobby.tld>
Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 9A3097B27AA for <username@surname.tld>; Tue, 24 Sep 2024 01:36:31 -0400 (EDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hobby.tld; s=dkim; t=1727156192; h=from:subject:date:message-id:to:mime-version:content-type:
content-transfer-encoding; bh=Xtq25R7aQrJM+lQ2YmHt3SeP2FPs3XulMyEA50TAaOo=; b=DKeGeWMkP1up4rcB7SB4tNDhia2w+iTEGGntG+KvWAaIz/VSuUwMzKdscbsa1wSZ9dG7+a y87JxEWVsbXdOf7cpQ0ktkr+LrrdFOEk/AbTo1TNeaP5fu2okhjpE3aXTC9mJzYvfWWVh/ GlKTmzSO1oyZoDJW0qNM+TCTy/y96lbQizBa6J/f7AGqgfcJDqlfiweAtmXUBZtPiZIy0Y zKgSIGUCalirffD30EyVmzZZbmNcw5dLs/3P8rpbDUkWPT7By6oYu6JFiHZQb7HsUCHHpV IMrBeKUdMqxSILgvPLyMHH192KOv8fDY2Zg6R9mh3/65GinqKQXm6/UgvGOXGA==
Received: by fluorine.localdomain (Postfix, from userid 0) id BB9C7A94A3; Tue, 24 Sep 2024 01:31:29 -0400 (EDT)
To: username@surname.tld
From: username@hobby.tld
Subject: Logwatch for fluorine (Linux)
Auto-Submitted: auto-generated
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/html; charset="UTF-8"
Message-Id: <20240924053129.BB9C7A94A3@fluorine.localdomain>
Date: Tue, 24 Sep 2024 01:31:29 -0400 (EDT)
X-Last-TLS-Session-Version: TLSv1.3
redacted logwatch HTML email
Now, I haven’t seen this email in a couple weeks, as the dates in the undeliverable message show. I didn’t do anything to fix it; and the logwatch message for today (2024-10-06) was delivered appropriately when I opened the lid to fuorine (my laptop) earlier this afternoon.
I’m really not sure how to go about troubleshooting this, as I don’t know where to begin looking at why mail.surname.tld rejected the message and sent the rejection notice to username@hobby.tld.