Email
修復我的 MTA 的不良聲譽
我有一個網站需要向客戶發送電子郵件以傳遞他們購買的文件。可靠的電子郵件傳遞對這項業務至關重要。不幸的是,由於我的 MTA 的“聲譽不佳”,我的伺服器發送的大多數電子郵件都沒有送達。以下是我的一些範例行
mail.log
:Feb 20 02:40:41 servername postfix/smtp[14580]: 4E30B1100C7: host aspmx.l.google.com[209.85.211.78] said: 421-4.7.0 [174.143.183.26] Our system has detected an unusual amount of 421-4.7.0 unsolicited mail originating from your IP address. To protect our 421-4.7.0 users from spam, mail sent from your IP address has been temporarily 421-4.7.0 blocked. Please visit http://www.google.com/mail/help/bulk_mail.html 421 4.7.0 to review our Bulk Email Senders Guidelines. 10si1216690ywh.92 (in reply to end of DATA command) Feb 20 12:49:22 servername postfix/smtp[5651]: A86CB1CC0CF: to=<user@domain.com>, relay=mx3.comcast.net[76.96.58.14]:25, delay=55186, delays=55185/0.01/0.93/0, dsn=4.0.0, status=deferred (host mx3.comcast.net[76.96.58.14] refused to talk to me: 554 imta36.westchester.pa.mail.comcast.net comcast 174.143.206.168 found on one or more DNSBLs, see http://help.comcast.net/content/faq/BL000001) Feb 16 10:50:11 servername postfix/smtp[6931]: 98B94380A1: host mx-in-2.webreus.nl[212.61.252.240] refused to talk to me: 554-mx-in-2.webreus.nl 554-Your access to this mail system has been rejected due to the sending MTA's poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means. 554 More information can be found on http://senderbase.org/senderbase_queries/detailhost?search_string=174.143.206.168 Feb 16 10:50:12 servername postfix/smtp[6931]: 98B94380A1: to=<user@domain.com>, relay=mx-in-1.webreus.nl[212.61.10.240]:25, delay=173653, delays=173650/0.22/2.8/0, dsn=4.0.0, status=deferred (host mx-in-1.webreus.nl[212.61.10.240] refused to talk to me: 554-mx-in-1.webreus.nl 554-Your access to this mail system has been rejected due to the sending MTA's poor reputation. If you believe that this failure is in error, please contact the intended recipient via alternate means. 554 More information can be found on http://senderbase.org/senderbase_queries/detailhost?search_string=174.143.206.168)
我為改善這種情況而採取的步驟:
- 設置反向 DNS 查找以正常工作
- 為我的域設置 SPF 記錄
- 禁止到我的 SMTP 伺服器的傳入連接
- 根據 RFC 2822 格式化消息
- 從不發送未經請求的消息(我從來沒有)
我的伺服器在 Rackspace 的雲中。IP地址的壞名聲是否可能是從以前的客戶那裡繼承下來的?過去一周已經採取了上述一些步驟——我是否必須等待情況好轉?還有其他我應該做的事情嗎?我應該聘請第三方為我發送電子郵件嗎?
不幸的是,無論其背後的硬體如何,IP 都被列入黑名單,因此除了確保您正確發送郵件並聯繫相關的垃圾郵件列表外,您對現有聲譽無能為力。您可能需要等待幾天或幾週才能改善情況。
我建議使用 Google Apps for SMTP 來消除這些問題 :)
否則,如果您繼續自己進行,請檢查:
- 你不在黑名單上
- 您的伺服器有MX 和反向 DNS 記錄
- 您有SPF DNS 記錄(許多伺服器拒絕沒有有效 SPF 的郵件,例如 GMail,這裡有一個解釋和一個嚮導)
- 您的郵件伺服器的HELO 響應與您的主機名匹配
- 您的郵件伺服器不是開放中繼
- 您的DNS 記錄的 TTL並不太低 - 建議使用 86400(24 小時)(一些垃圾郵件發送者將其 TTL 設置得很低以定期更新偽造的 DNS 記錄)
- 您遵守AOL 的技術標準