我剛剛在 CentOS 7 上使用 Postfix 設定了一個新的郵件伺服器，該機器充當兩個網域（domain1.com 和 domain2.com）的 mx。伺服器的主機名稱是domain1.com，並且具有正確的PTR記錄集。兩個網域都將其唯一的 MX 記錄指向domain1，並且都具有正確的 DKIM 和 SPF 記錄。
問題在於，從地址 @domain2.com 發送的郵件始終被 GMail 標記為垃圾郵件，而從 @domain1.com 發送的完全相同的郵件則不然。
以下是 dig 輸出的一些 DNS 記錄。
域1
domain1.com. 300 IN A 1.2.3.4
domain1.com. 300 IN MX 1 domain1.com.
domain1.com. 300 IN TXT "v=spf1 mx ~all"
default._domainkey.domain1.com 300 IN TXT "v=DKIM1\; k=rsa\; p=<blurp>"
1.2.3.4 的反向 DNS
4.3.2.1.in-addr.arpa. 3600 IN PTR domain1.com
域2
domain2.com. 300 IN A 1.2.3.4
domain2.com. 300 IN MX 1 domain1.com.
domain2.com. 300 IN TXT "v=spf1 mx ~all"
default._domainkey.domain2.com. 300 IN TXT "v=DKIM1\; k=rsa\; p=<blurp>"
SMTP 伺服器對 EHLO 做出以下回應：
220 domain1.com ESMTP Postfix
EHLO banana
250-domain1.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH PLAIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
同樣，問題是從 @domain2.com 發送的完全相同的郵件被標記為垃圾郵件，但從 @domain1.com 發送的郵件則不然。我嘗試透過多個 DKIM 和 SPF 驗證器運行整個設置，並且還根據多個黑名單檢查了 IP。此外，我在 mxtoolbom.com 上運行了所有測試，這些工具都沒有報告任何問題。
以下是 GMail 看到的由同一用戶分別從domain1.com 和domain2.com 發送的兩封電子郵件：
非垃圾郵件 (@domain1)
Delivered-To: [email protected]
Received: by 10.60.57.165 with SMTP id j5csp382145oeq;
Tue, 28 Oct 2014 06:11:12 -0700 (PDT)
X-Received: by 10.112.168.2 with SMTP id zs2mr3138752lbb.25.1414501871638;
Tue, 28 Oct 2014 06:11:11 -0700 (PDT)
Return-Path: <[email protected]>
Received: from domain1.com (domain1.com. [1.2.3.4])
by mx.google.com with ESMTP id lm8si2545487lac.7.2014.10.28.06.11.10
for <[email protected]>;
Tue, 28 Oct 2014 06:11:11 -0700 (PDT)
Received-SPF: pass (google.com: domain of [email protected] designates 1.2.3.4 as permitted sender) client-ip=1.2.3.4;
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of [email protected] designates 1.2.3.4 as permitted sender) [email protected];
dkim=pass [email protected]
Received: by domain1.com (Postfix, from userid 1001)
id 7104140D41; Tue, 28 Oct 2014 14:11:10 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=domain1.com;
s=default; t=1414501870;
bh=6ycM+eq5HvFTqqe79TLije21S91XFijH+fOKPHMU5Zc=;
h=From:Subject:Date:To;
b=<blurp>
X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on domain2.com
X-Spam-Level:
X-Spam-Status: No, score=-1.1 required=5.0 tests=ALL_TRUSTED,DKIM_SIGNED,
DKIM_VALID,DKIM_VALID_AU,URIBL_BLOCKED autolearn=ham version=3.3.2
Received: from [192.168.178.63] (dsl.provider.com [100.100.100.100])
by domain1.com (Postfix) with ESMTPSA id 726E140D09
for <[email protected]>; Tue, 28 Oct 2014 14:11:05 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=domain1.com;
s=default; t=1414501865;
bh=6ycM+eq5HvFTqqe79TLije21S91XFijH+fOKPHMU5Zc=;
h=From:Subject:Date:To;
b=<blurp>
From: That Guy <[email protected]>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Subject: Yellow Bananas
Message-Id: <[email protected]>
Date: Tue, 28 Oct 2014 14:11:05 +0100
To: [email protected]
Mime-Version: 1.0 (Mac OS X Mail 8.0 \(1990.1\))
X-Mailer: Apple Mail (2.1990.1)
Hi,
Do not forget to buy some bananas!
標記為跨距 (@domain2.com)
Delivered-To: [email protected]
Received: by 10.60.57.165 with SMTP id j5csp382123oeq;
Tue, 28 Oct 2014 06:11:01 -0700 (PDT)
X-Received: by 10.112.167.130 with SMTP id zo2mr4018217lbb.4.1414501861369;
Tue, 28 Oct 2014 06:11:01 -0700 (PDT)
Return-Path: <[email protected]>
Received: from domain1.com (domain1.com. [1.2.3.4])
by mx.google.com with ESMTP id mj1si2507360lbc.40.2014.10.28.06.11.00
for <[email protected]>;
Tue, 28 Oct 2014 06:11:01 -0700 (PDT)
Received-SPF: pass (google.com: domain of [email protected] designates 1.2.3.4 as permitted sender) client-ip=1.2.3.4;
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of [email protected] designates 1.2.3.4 as permitted sender) [email protected];
dkim=pass [email protected]
Received: by domain1.com (Postfix, from userid 1001)
id E816D40D41; Tue, 28 Oct 2014 14:10:59 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=domain2.com;
s=default; t=1414501859;
bh=6ycM+eq5HvFTqqe79TLije21S91XFijH+fOKPHMU5Zc=;
h=From:Subject:Date:To;
b=<blurp>
X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on domain2.com
X-Spam-Level:
X-Spam-Status: No, score=-1.1 required=5.0 tests=ALL_TRUSTED,DKIM_SIGNED,
DKIM_VALID,DKIM_VALID_AU,URIBL_BLOCKED autolearn=ham version=3.3.2
Received: from [192.168.178.63] (dsl.provider.com [100.100.100.100])
by domain1.com (Postfix) with ESMTPSA id F326840D09
for <[email protected]>; Tue, 28 Oct 2014 14:10:54 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=domain2.com;
s=default; t=1414501855;
bh=6ycM+eq5HvFTqqe79TLije21S91XFijH+fOKPHMU5Zc=;
h=From:Subject:Date:To;
b=<blurp>
From: That Guy <[email protected]>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Subject: Yellow Bananas
Message-Id: <[email protected]>
Date: Tue, 28 Oct 2014 14:10:53 +0100
To: [email protected]
Mime-Version: 1.0 (Mac OS X Mail 8.0 \(1990.1\))
X-Mailer: Apple Mail (2.1990.1)
Hi,
Do not forget to buy some bananas!
根據 Google 的說法，阻止第二封郵件的原因是：“為什麼此郵件在垃圾郵件中？它與我們的垃圾郵件過濾器檢測到的郵件類似。了解更多”，這是一個鏈接https://support.google.com/mail/answer/1366858?hl=zh-CN&expand=5。
我已經研究了幾個小時了，但我似乎無法弄清楚這一點。我按照 Google 在大量電子郵件指南中建議的所有操作進行了操作。