port25.com通过发送电子邮件到
check-auth@verifier.port25.com使用的漂亮小工具测试我的 SPF 记录时，我得到以下 FAIL 结果：
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Details:
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HELO hostname: avantgardeweb.co.uk
Source IP: 2002:2e20:e862::2e20:e862
mail-from: user@greenshieldsarchitecture.co.uk
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SPF check details:
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Result: fail (not permitted)
ID(s) verified: smtp.mailfrom=user@greenshieldsarchitecture.co.uk
DNS record(s):
greenshieldsarchitecture.co.uk. SPF (no records)
greenshieldsarchitecture.co.uk. 14400 IN TXT "v=spf1 mx a -all"
greenshieldsarchitecture.co.uk. 14400 IN MX 10 mail.greenshieldsarchitecture.co.uk.
mail.greenshieldsarchitecture.co.uk. AAAA (no records)
greenshieldsarchitecture.co.uk. AAAA (no records)
但是，当我实际向 gmail 帐户发送电子邮件时，它会通过：
Received-SPF: pass (google.com: domain of user@greenshieldsarchitecture.co.uk designates 46.32.232.98 as permitted sender) client-ip=46.32.232.98;
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of user@greenshieldsarchitecture.co.uk …