介绍
我最近安装了后缀 3.3.0在 Ubuntu 18.04.3 LTS 虚拟机上。
为了测试安装，我使用开箱即用的配置，这意味着我没有更改任何事物还没有。仅在安装期间，我选择Internet site并插入了我的 fqdn example.com。我希望能够从我的域发送和发送电子邮件。简单来说，一台服务器处理所有邮件。
假设我的域名是example.com。
正在发送
我可以发出电子邮件已成功发送。我尝试从我的服务器发送电子邮件。在我的 Gmail 收件箱中，我可以看到发件人地址是。发送部分一切正常。sendmail [email protected][email protected]
接收
我还可以接收来自一些我测试过的地址的电子邮件。从日志中可以看出/var/log/mail.log：
Nov 11 21:57:44 mail postfix/smtpd[24956]: connect from f175.i.mail.ru[94.100.178.161]
Nov 11 21:57:44 mail postfix/smtpd[24956]: EB5DA459A4: client=f175.i.mail.ru[94.100.178.161]
Nov 11 21:57:45 mail postfix/cleanup[24959]: EB5DA459A4: message-id=<[email protected]>
Nov 11 21:57:45 mail postfix/qmgr[24610]: EB5DA459A4: from=<[email protected]>, size=2917, nrcpt=1 (queue active)
Nov 11 21:57:45 mail postfix/local[24960]: EB5DA459A4: to=<[email protected]>, relay=local, delay=0.09, delays=0.08/0/0/0.01, dsn=2.0.0, status=sent (delivered to mailbox)
Nov 11 21:57:45 mail postfix/qmgr[24610]: EB5DA459A4: removed
Nov 11 21:57:45 mail postfix/smtpd[24956]: disconnect from f175.i.mail.ru[94.100.178.161] ehlo=2 starttls=1 mail=1 rcpt=1 data=1 quit=1 commands=7
问题是，我无法接收来自 gmail 的邮件。当我从我的 gmail 帐户向 发送电子邮件时[email protected]，几秒钟后我的服务器中会出现以下日志：
Nov 12 08:30:25 mail postfix/smtpd[28230]: connect from mail-wr1-f44.google.com[209.85.221.44]
Nov 12 08:30:25 mail postfix/smtpd[28230]: NOQUEUE: reject: RCPT from mail-wr1-f44.google.com[209.85.221.44]: 454 4.7.1 <[email protected]>: Relay access denied; from=<[email protected]> to=<[email protected]> proto=ESMTP helo=<mail-wr1-f44.google.com>
Nov 12 08:30:25 mail postfix/smtpd[28230]: disconnect from mail-wr1-f44.google.com[209.85.221.44] ehlo=2 starttls=1 mail=1 rcpt=0/1 data=0/1 quit=1 commands=5/7
我想了解的是，这是我这边的配置问题，还是这个错误发生在 Gmail 服务器中，然后转发到我的服务器以让我知道？
我该如何尝试修复此问题？
什么样的最小、最干净的工作配置能够让我能够像普通邮件服务器一样与所有其他外部邮件服务器进行发送和传递？
编辑
根据要求，以下是/etc/postfix/main.cf：
# 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 $mail_name (Ubuntu)
biff = no
# appending .domain is the MUA's job.
append_dot_mydomain = no
# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h
readme_directory = no
# See http://www.postfix.org/COMPATIBILITY_README.html -- default to 2 on
# fresh installs.
compatibility_level = 2
# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache
# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.
smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
mydomain = example.com
myhostname = mail.$mydomain
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = $mydomain
mydestination = $myhostname, $mydomain, localhost, localhost.localdomain
relayhost =
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all
正如您所看到的，仅有的到目前为止，我对默认配置所做的更改是对mydomain、myorigin和变量myhostname的更改mydestination，如上所示。问题完全相同。
编辑2
这是/etc/postfix/master.cf文件（我没有编辑它）：
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master" or
# on-line: http://www.postfix.org/master.5.html).
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (no) (never) (100)
# ==========================================================================
smtp inet n - y - - smtpd
#smtp inet n - y - 1 postscreen
#smtpd pass - - y - - smtpd
#dnsblog unix - - y - 0 dnsblog
#tlsproxy unix - - y - 0 tlsproxy
#submission inet n - y - - smtpd
# -o syslog_name=postfix/submission
# -o smtpd_tls_security_level=encrypt
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_tls_auth_only=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
# -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=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
# -o milter_macro_daemon_name=ORIGINATING
#628 inet n - y - - qmqpd
pickup unix n - y 60 1 pickup
cleanup unix n - y - 0 cleanup
qmgr unix n - n 300 1 qmgr
#qmgr unix n - n 300 1 oqmgr
tlsmgr unix - - y 1000? 1 tlsmgr
rewrite unix - - y - - trivial-rewrite
bounce unix - - y - 0 bounce
defer unix - - y - 0 bounce
trace unix - - y - 0 bounce
verify unix - - y - 1 verify
flush unix n - y 1000? 0 flush
proxymap unix - - n - - proxymap
proxywrite unix - - n - 1 proxymap
smtp unix - - y - - smtp
relay unix - - y - - smtp
-o syslog_name=postfix/$service_name
# -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}
答案1
问题已部分解决，但根据我发布的问题，这是不可能的。很抱歉。问题中没有包含导致问题根源的信息，因为当时看起来无关紧要。
我的域名example.com实际上包含非 ASCII 字符，因此它有两种形式，原始形式如üüü.com和编码形式如xn--tdaaa.com。虽然它们都指向同一个域，但 Postfix 认为它们是不同的。根据以下两种情况之一，接受邮件可能会成功或失败：
当发送 SMTP 请求时，如果收件人采用其编码形式（例如）
xn--tdaaa.com，则一切正常（例如 mail.ru 就是这样做的，如上面的问题所示）。当 SMTP 请求以原始格式（例如）发送时
üüü.com，电子邮件会被拒绝，因为它与配置中指定的域名不匹配。此外，无法ü在配置中包含字符，因为 postfix 会抱怨使用了无效字符。
Gmail 总是以非编码形式发送邮件üüü.com，无论您在指定收件人时是否使用编码形式。因此，除非有办法配置 postfix 以理解 IDN，否则根本不可能从 gmail 发送邮件。