작은 행복을 위한 시

최근들어 SSL 도입이 늘어나면서 조금씩 문제들이 발생하고 있다.

메일을 보냈는데 회신이 없어 확인해 보니 반송 메일이 스팸함에 들어 있었다.

 ----- Transcript of session follows -----
<
xxxxx@xxxxxxxxx.co.kr
>... Deferred: 403 4.7.0 TLS handshake failed.
Warning: message still undelivered after 4 hours
Will keep trying until message is 5 days old

해결방법은
/etc/mail/access에 아래를 추가해 주면 된다.

Try_TLS:xxxxxxxxx.co.kr NO

How to fix the error ‘403 4.7.0 TLS handshake failed’ in RedHat, CentOS and OpenSuse servers with Sendmail

Along with the error message “403 4.7.0 TLS handshake failed”, it is possible to identify the recipient domain which has the TLS connectivity issue.

Edit the configuration file “/etc/mail/access” and add the line:

Try_TLS:domain.com NO

Since “/etc/mail/access” is a database, after creating that text file and editing it, use ‘makemap‘ to create the database map.

makemap hash /etc/mail/access.db < /etc/mail/access

Restart the mail server. This will exempt that domain from TLS email transmission and the mails would deliver fine without errors.

<참고사이트>
https://www.raramuridesign.com/kb/articles/hes-how-to-fix-email-error-403-4-7-0-tls-handshake-failed-in-cpanel-plesk-exim-qmail-exchange-and-sendmail-servers.html

#메일 #mail #TLS #HandshakeFailed #CentOS

운영중인 postfix 메일 서버에 TLS 접속이, 어떤 버전으로 얼마나 접속하는지 궁금하다면,
아래와 같이 확인해 보자.

# grep 'TLS connection established from' mail.log |sed 's/^.*: \(TLSv[^]*\).*/\1/' |sort |uniq -c
1285 TLSv1
    2 TLSv1.1
4997 TLSv1.2