我为我的 Ubuntu 16.04 电子邮件服务器设置了 Postfix + Dovecot（带 IMAP）。我从 Gmail 向我的域发送了一封电子邮件，我可以看到 postfix 日志对收到的电子邮件“做出反应”，但收到的电子邮件并未出现在邮箱中。
以下是日志的相关部分：
Mar 30 02:15:17 yourappapp-vm postfix/smtp[27680]: Untrusted TLS connection established to gmail-smtp-in.l.google.com[74.125.24.27]:25: TLSv1.2 with cipher ECDHE-ECDSA-AES128-GCM-SHA256 (128/128 bits)
Mar 30 02:15:18 yourappapp-vm postfix/smtp[27680]: C5EBB1BCB3B: to=<[email protected]>, orig_to=<[email protected]>, relay=gmail-smtp-in.l.google.com[74.125.24.27]:25, delay=1.3, delays=0/0.01/0.7/0.63, dsn=2.0.0, status=sent (250 2.0.0 OK 1617070518 y128si20297886pfb.155 - gsmtp)
Mar 30 02:15:18 yourappapp-vm postfix/qmgr[27605]: C5EBB1BCB3B: removed
看起来这是一封外发邮件，但我当时没有发送任何内容。我只有在从 Gmail 发送电子邮件时才收到此邮件。我该如何进一步调试？
ps 对于不受信任的 TLS 问题，我已通过在 Postfix 配置中添加 CApath 来修复它。邮箱中仍然没有电子邮件。
在我的~/Maildir/子文件夹中，全部都是空的。
ps：邮件服务器可以发送电子邮件，因此 SMTP 部分没有问题。
更多调试信息如下：
网络端口
Postfix 正在监听 25、587 和 465
$ ss -lnpt | grep master
LISTEN 0 100 *:25 *:* users:(("master",pid=27603,fd=12))
LISTEN 0 100 *:587 *:* users:(("master",pid=27603,fd=16))
LISTEN 0 100 *:465 *:* users:(("master",pid=27603,fd=19))
Dovecot 正在收听 143 和 993
$ ss -lnpt | grep dovecot
LISTEN 0 100 *:993 *:* users:(("dovecot",pid=27649,fd=36))
LISTEN 0 100 *:143 *:* users:(("dovecot",pid=27649,fd=35))
主配置文件
# See /usr/share/postfix/main.cf.dist for a commented, more complete version
# Debian specific: Specifying a file name will cause the first
# line of that file to be used as the name. The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname
smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
biff = no
# appending .domain is the MUA's job.
append_dot_mydomain = no
# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h
readme_directory = no
# TLS parameters
#smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
#smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
#Enable TLS Encryption when Postfix receives incoming emails
smtpd_tls_cert_file=/etc/letsencrypt/live/mail.yourappapp.com/fullchain.pem
smtpd_tls_key_file=/etc/letsencrypt/live/mail.yourappapp.com/privkey.pem
smtpd_tls_security_level=may
smtpd_tls_loglevel = 1
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
#Enable TLS Encryption when Postfix sends outgoing emails
smtp_tls_security_level = may
smtp_tls_loglevel = 1
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
#Enforce TLSv1.3 or TLSv1.2
smtpd_tls_mandatory_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1
smtpd_tls_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1
smtp_tls_mandatory_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1
smtp_tls_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
smtp_tls_CApath = /etc/ssl/certs
smtpd_tls_CApath = /etc/ssl/certs
# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.
smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
myhostname = mail.yourappapp.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = yourappapp.com, $myhostname, localhost.$mydomain, localhost
relayhost =
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = ipv4
home_mailbox = Maildir/
# LMTP
mailbox_transport = lmtp:unix:private/dovecot-lmtp
smtputf8_enable = no
mydomain = yourappapp.com
主配置文件
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master" or
# on-line: http://www.postfix.org/master.5.html).
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (no) (never) (100)
# ==========================================================================
smtp inet n - y - - smtpd
#smtp inet n - y - 1 postscreen
#smtpd pass - - y - - smtpd
#dnsblog unix - - y - 0 dnsblog
#tlsproxy unix - - y - 0 tlsproxy
submission inet n - y - - smtpd
-o syslog_name=postfix/submission
-o smtpd_tls_security_level=encrypt
-o smtpd_tls_wrappermode=no
-o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
-o smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject
-o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o smtpd_sasl_type=dovecot
-o smtpd_sasl_path=private/auth
# -o milter_macro_daemon_name=ORIGINATING
smtps inet n - y - - smtpd
-o syslog_name=postfix/smtps
-o smtpd_tls_wrappermode=yes
-o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
-o smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject
-o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o smtpd_sasl_type=dovecot
-o smtpd_sasl_path=private/auth
# -o milter_macro_daemon_name=ORIGINATING
#628 inet n - y - - qmqpd
pickup unix n - y 60 1 pickup
cleanup unix n - y - 0 cleanup
qmgr unix n - n 300 1 qmgr
#qmgr unix n - n 300 1 oqmgr
tlsmgr unix - - y 1000? 1 tlsmgr
rewrite unix - - y - - trivial-rewrite
bounce unix - - y - 0 bounce
defer unix - - y - 0 bounce
trace unix - - y - 0 bounce
verify unix - - y - 1 verify
flush unix n - y 1000? 0 flush
proxymap unix - - n - - proxymap
proxywrite unix - - n - 1 proxymap
smtp unix - - y - - smtp
relay unix - - y - - smtp
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
showq unix n - y - - showq
error unix - - y - - error
retry unix - - y - - error
discard unix - - y - - discard
local unix - n n - - local
virtual unix - n n - - virtual
lmtp unix - - y - - lmtp
anvil unix - - y - 1 anvil
scache unix - - y - 1 scache
#
# ====================================================================
# Interfaces to non-Postfix software. Be sure to examine the manual
# pages of the non-Postfix software to find out what options it wants.
#
# Many of the following services use the Postfix pipe(8) delivery
# agent. See the pipe(8) man page for information about ${recipient}
# and other message envelope options.
# ====================================================================
#
# maildrop. See the Postfix MAILDROP_README file for details.
# Also specify in main.cf: maildrop_destination_recipient_limit=1
#
maildrop unix - n n - - pipe
flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient}
#
# ====================================================================
#
# Recent Cyrus versions can use the existing "lmtp" master.cf entry.
#
# Specify in cyrus.conf:
# lmtp cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4
#
# Specify in main.cf one or more of the following:
# mailbox_transport = lmtp:inet:localhost
# virtual_transport = lmtp:inet:localhost
#
# ====================================================================
#
# Cyrus 2.1.5 (Amos Gouaux)
# Also specify in main.cf: cyrus_destination_recipient_limit=1
#
#cyrus unix - n n - - pipe
# user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user}
#
# ====================================================================
# Old example of delivery via Cyrus.
#
#old-cyrus unix - n n - - pipe
# flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user}
#
# ====================================================================
#
# See the Postfix UUCP_README file for configuration details.
#
uucp unix - n n - - pipe
flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
#
# Other external delivery methods.
#
ifmail unix - n n - - pipe
flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp unix - n n - - pipe
flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient
scalemail-backend unix - n n - 2 pipe
flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} ${user} ${extension}
mailman unix - n n - - pipe
flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
${nexthop} ${user}
SMTP 会话看起来也很好：
220 mail.yourappapp.com ESMTP Postfix (Ubuntu)
250 mail.yourappapp.com
EHLO test.network-tools.com
250-mail.yourappapp.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
VRFY info
252 2.0.0 info
RSET
250 2.0.0 Ok
EXPN info
502 5.5.2 Error: command not recognized
RSET
250 2.0.0 Ok
MAIL FROM:<[email protected]>
250 2.1.0 Ok
RCPT TO:<[email protected]>
250 2.1.5 Ok
RSET
250 2.0.0 Ok
QUIT
根据答案添加了调试信息：
Telnet 会话日志
$ telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 mail.yourappapp.com ESMTP Postfix (Ubuntu)
HELO localhost
250 mail.yourappapp.com
MAIL FROM: <[email protected]>
250 2.1.0 Ok
RCPT TO: <[email protected]>
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
From: <[email protected]>
To: <[email protected]>
Subject: Test from Telnet
This is a test
.
250 2.0.0 Ok: queued as BB9021B9B62
QUIT
221 2.0.0 Bye
Connection closed by foreign host.
相关邮件日志
Mar 31 01:43:27 yourappapp-vm postfix/smtpd[8491]: connect from localhost[127.0.0.1]
Mar 31 01:43:54 yourappapp-vm postfix/smtpd[8491]: BB9021B9B62: client=localhost[127.0.0.1]
Mar 31 01:44:31 yourappapp-vm postfix/cleanup[8494]: BB9021B9B62: message-id=<[email protected]>
Mar 31 01:44:31 yourappapp-vm postfix/qmgr[32352]: BB9021B9B62: from=<[email protected]>, size=391, nrcpt=1 (queue active)
Mar 31 01:44:31 yourappapp-vm postfix/cleanup[8494]: 9636F1B9B63: message-id=<[email protected]>
Mar 31 01:44:31 yourappapp-vm postfix/qmgr[32352]: 9636F1B9B63: from=<[email protected]>, size=526, nrcpt=1 (queue active)
Mar 31 01:44:31 yourappapp-vm postfix/local[8498]: BB9021B9B62: to=<[email protected]>, relay=local, delay=45, delays=45/0/0/0, dsn=2.0.0, status=sent (forwarded as 9636F1B9B63)
Mar 31 01:44:31 yourappapp-vm postfix/qmgr[32352]: BB9021B9B62: removed
Mar 31 01:44:32 yourappapp-vm postfix/smtp[8499]: Trusted TLS connection established to gmail-smtp-in.l.google.com[172.217.194.27]:25: TLSv1.2 with cipher ECDHE-ECDSA-AES128-GCM-SHA256 (128/128 bits)
Mar 31 01:44:33 yourappapp-vm postfix/smtp[8499]: 9636F1B9B63: to=<[email protected]>, orig_to=<[email protected]>, relay=gmail-smtp-in.l.google.com[172.217.194.27]:25, delay=1.4, delays=0/0.01/0.69/0.71, dsn=2.0.0, status=sent (250 2.0.0 OK 1617155072 u21si587511pfl.125 - gsmtp)
Mar 31 01:44:33 yourappapp-vm postfix/qmgr[32352]: 9636F1B9B63: removed
Mar 31 01:44:35 yourappapp-vm postfix/smtpd[8491]: disconnect from localhost[127.0.0.1] helo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
两个日志看起来都很正常，但是邮箱中没有收到任何电子邮件。
答案1
当您已经测试 smtp 连接时，您也可以使用 telnet 测试电子邮件传递：
telnet localhost 25
HELO localhost
MAIL FROM: <[email protected]>
RCPT TO: <[email protected]>
DATA
From: <[email protected]>
To: <[email protected]>
Subject: test
This is a test
.
QUIT
发生了什么事？
否则，在我看来，这实际上是一封外发邮件，如果有任何传入连接，它一定在问题中提供的线之上。这可能是一个错误/退回。
编辑：感谢您的额外调试，让我们关注以下部分：
Mar 31 01:44:31 yourappapp-vm postfix/local[8498]: BB9021B9B62: to=<[email protected]>, relay=local, delay=45, delays=45/0/0/0, dsn=2.0.0, status=sent (forwarded as 9636F1B9B63)
Mar 31 01:44:31 yourappapp-vm postfix/qmgr[32352]: BB9021B9B62: removed
Mar 31 01:44:32 yourappapp-vm postfix/smtp[8499]: Trusted TLS connection established to gmail-smtp-in.l.google.com[172.217.194.27]:25: TLSv1.2 with cipher ECDHE-ECDSA-AES128-GCM-SHA256 (128/128 bits)
Mar 31 01:44:33 yourappapp-vm postfix/smtp[8499]: 9636F1B9B63: to=<[email protected]>, orig_to=<[email protected]>, relay=gmail-smtp-in.l.google.com[172.217.194.27]:25, delay=1.4, delays=0/0.01/0.69/0.71, dsn=2.0.0, status=sent (250 2.0.0 OK 1617155072 u21si587511pfl.125 - gsmtp)
首先，您可以看到relay=local和status=sent，因此该电子邮件实际上是在本地被接受的。使用的是本地投递。有趣的部分从那之后开始forwarded as- 这通常不会发生在本地电子邮件中。
下一个有趣的部分是确认无论交付给什么，都会被进一步转发回to=<[email protected]>, orig_to=<[email protected]>,[email protected][电子邮件保护]。
我很好奇你的/etc/aliases文件中有什么。通常电子邮件不会被转发回去。它看起来像是一个休假脚本或别名或我在提供的配置文件中看不到的其他机制。