发送电子邮件至[电子邮件保护]通过我自己的 SMTP 服务器 (mail.sarit.be)，接收邮件服务器回复：
451 #4.1.8 Domain of sender address <[email protected]> does not resolve
从我的 postfix 日志来看，所有接收 MX 服务器都无法解析 sarit.be 或 mail.sarit.be。
;; QUESTION SECTION:
;terremark.com. IN MX
;; ANSWER SECTION:
terremark.com. 300 IN MX 15 fldsmtpe04.verizon.com.
terremark.com. 300 IN MX 15 fldsmtpe01.verizon.com.
terremark.com. 300 IN MX 15 fldsmtpe02.verizon.com.
terremark.com. 300 IN MX 15 fldsmtpe03.verizon.com.
Aug 6 08:47:42 charlie postfix/smtp[22257]: 2A45D2D56: to=<[email protected]>, relay=fldsmtpe01.verizon.com[140.108.26.140]:25, delay=418619, delays=418496/0.01/63/60, dsn=4.0.0, status=deferred (host fldsmtpe01.verizon.com[140.108.26.140] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command))
Aug 6 09:56:41 charlie postfix/smtp[22866]: 2A45D2D56: host fldsmtpe02.verizon.com[140.108.26.141] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command)
Aug 6 09:57:44 charlie postfix/smtp[22866]: 2A45D2D56: to=<[email protected]>, relay=fldsmtpe03.verizon.com[140.108.26.142]:25, delay=422821, delays=422697/0.01/64/60, dsn=4.0.0, status=deferred (host fldsmtpe03.verizon.com[140.108.26.142] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command))
Aug 6 11:06:42 charlie postfix/smtp[23660]: 2A45D2D56: host fldsmtpe01.verizon.com[140.108.26.140] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command)
Aug 6 11:07:44 charlie postfix/smtp[23660]: 2A45D2D56: to=<[email protected]>, relay=fldsmtpe03.verizon.com[140.108.26.142]:25, delay=427021, delays=426897/0.01/64/60, dsn=4.0.0, status=deferred (host fldsmtpe03.verizon.com[140.108.26.142] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command))
Aug 6 12:16:42 charlie postfix/smtp[24312]: 2A45D2D56: host fldsmtpe04.verizon.com[140.108.26.143] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command)
Aug 6 12:17:43 charlie postfix/smtp[24312]: 2A45D2D56: to=<[email protected]>, relay=fldsmtpe02.verizon.com[140.108.26.141]:25, delay=431221, delays=431097/0.01/63/60, dsn=4.0.0, status=deferred (host fldsmtpe02.verizon.com[140.108.26.141] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command))
Aug 6 13:26:42 charlie postfix/smtp[24956]: 2A45D2D56: host fldsmtpe02.verizon.com[140.108.26.141] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command)
Aug 6 13:27:43 charlie postfix/smtp[24956]: 2A45D2D56: to=<[email protected]>, relay=fldsmtpe04.verizon.com[140.108.26.143]:25, delay=435420, delays=435297/0.01/63/60, dsn=4.0.0, status=deferred (host fldsmtpe04.verizon.com[140.108.26.143] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command))
Aug 8 08:21:34 charlie postfix/smtp[15495]: 46D6E6353: host fldsmtpe03.verizon.com[140.108.26.142] said: 451 #4.1.8 Domain of sender address <[email protected]> does not resolve (in reply to MAIL FROM command)
我已验证我的 MX 服务器的反向 DNS 查找和 sarit.be 域的 SPF 记录。
;; QUESTION SECTION:
;sarit.be. IN MX
;; ANSWER SECTION:
sarit.be. 3600 IN MX 10 mail.sarit.be.
;; QUESTION SECTION:
;mail.sarit.be. IN A
;; ANSWER SECTION:
mail.sarit.be. 2128 IN A 176.9.7.243
;; QUESTION SECTION:
;243.7.9.176.in-addr.arpa. IN PTR
;; ANSWER SECTION:
243.7.9.176.in-addr.arpa. 43200 IN PTR mail.sarit.be.
;; QUESTION SECTION:
;sarit.be. IN SPF
;; ANSWER SECTION:
sarit.be. 3600 IN SPF "v=spf1 +a +mx ~all"
最后，我对我自己的邮件服务器和另一个 MX 服务器之间的 SMTP 流量进行了 tcpdump：
220 fldsmtpe01.verizon.com ESMTP
EHLO mail.sarit.be
250-fldsmtpe01.verizon.com
250-8BITMIME
250-SIZE 20971520
250 STARTTLS
MAIL FROM:<[email protected]> SIZE=537
451 #4.1.8 Domain of sender address <[email protected]> does not resolve
RSET
250 reset
QUIT
221 fldsmtpe01.verizon.com
我没有发现我的 DNS 有什么问题。我可以毫无困难地向其他域发送电子邮件。很容易认为错误出在接收邮件服务器上。您觉得呢？
PS：在这种情况下，反向 DNS 似乎并不那么重要，因为当我从[电子邮件保护]到[电子邮件保护]，即使这些 MX 服务器的正向/反向查找不匹配，电子邮件也会被接受。
答案1
这看起来像是接收方的临时 DNS 问题。他们的服务器由于某种原因无法解析您的地址。我认为您这边无法解决这个问题。您可能应该使用另一封电子邮件联系他们的代表并要求他们解决此问题。