我有一个使用 server.app 运行的 OS X 邮件服务器。它在后台运行 Postfix。最近，我的邮件队列一直堵塞，我不太清楚原因。我会尝试使用 强制队列sudo postqueue -f，但它不会做任何事情。让服务器处理队列的唯一方法是重新启动系统。
邮件服务器可以正常工作 2-3 天，然后又会开始堵塞。这或多或少迫使我每 2-3 天重新启动一次系统，以确保邮件能够送达。
如果我运行mailq，第一个条目如下所示：
0410E1878AAF 16737 Wed Jul 22 11:38:06 [email protected]
(host 127.0.0.1[127.0.0.1] said: 451 4.5.0 id=77854-02 - Temporary MTA failure on relaying, From MTA() during fwd-connect (All attempts (1) failed connecting to smtp:[127.0.0.1]:10025): id=77854-02 (in reply to end of DATA command))
[email protected]
所有后续条目如下所示：
048E21879841 16926 Wed Jul 22 13:07:16 [email protected]
(connect to 127.0.0.1[127.0.0.1]:10024: Can't assign requested address)
[email protected]
如果我查看/var/log/mail.log第一个条目发生的时间，我会看到以下内容：
Jul 22 11:38:06 mymailserver.com postfix/postscreen[73556]: CONNECT from [198.52.135.223]:39777 to [MYSERVER'SIPADDRESS]:25
Jul 22 11:38:06 mymailserver.com postfix/postscreen[73556]: PREGREET 29 after 0.08 from [198.52.135.223]:39777: EHLO shunpiking.mexilar.xyz\r\n
Jul 22 11:38:06 mymailserver.com postfix/smtpd[73557]: connect from shunpiking.mexilar.xyz[198.52.135.223]
Jul 22 11:42:52 mymailserver.com postfix/anvil[73561]: statistics: max connection rate 1/60s for (smtpd:198.52.135.223) at Jul 22 11:38:06
Jul 22 11:42:52 mymailserver.com postfix/anvil[73561]: statistics: max connection count 1 for (smtpd:198.52.135.223) at Jul 22 11:38:06
Jul 22 11:42:52 mymailserver.com postfix/anvil[73561]: statistics: max cache size 1 at Jul 22 11:38:06
我在上面的 mail.log 条目中删除了服务器的实际主机名和 IP 地址。
在我看来，服务器正在遭受重击并试图限制自己的速率，但我不明白为什么一切都关闭了。有人知道如何修复这个问题吗？
编辑：
这是来自的 master.cf 文件/Library/Server/Mail/Config/postfix/master.cf：
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master").
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (yes) (never) (100)
# ==========================================================================
# ==== Begin auto-generated section ========================================
# This section of the master.cf file is auto-generated by the Server Admin
# Mail backend plugin whenever mails settings are modified.
smtp inet n - n - 1 postscreen
smtpd pass - - n - - smtpd
-o receive_override_options=no_address_mappings
dnsblog unix - - n - 0 dnsblog
tlsproxy unix - - n - 0 tlsproxy
submission inet n - n - - smtpd
-o smtpd_tls_security_level=encrypt
smtp unix - - n - - smtp
# === End auto-generated section ===========================================
proxywrite unix - - n - 1 proxymap
# Modern SMTP clients communicate securely over port 25 using the STARTTLS command.
# Some older clients, such as Outlook 2000 and its predecessors, do not properly
# support this command and instead assume a preconfigured secure connection
# on port 465. This was sometimes called "smtps", but such usage was never
# approved by the IANA and therefore conflicts with another, legitimate assignment.
# For more details about managing secure SMTP connections with postfix, please see:
# http://www.postfix.org/TLS_README.html
# To read more about configuring secure connections with Outlook 2000, please read:
# http://support.microsoft.com/default.aspx?scid=kb;en-us;Q307772
# Apple does not support the use of port 465 for this purpose.
# After determining that connecting clients do require this behavior, you may choose
# to manually enable support for these older clients by uncommenting the following
# four lines.
#465 inet n - n - - smtpd
# -o smtpd_tls_wrappermode=yes
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_client_restrictions=permit_sasl_authenticated,reject
# -o milter_macro_daemon_name=ORIGINATING
#628 inet n - n - - qmqpd
pickup fifo n - n 60 1 pickup
-o content_filter=smtp-amavis:[127.0.0.1]:10024
cleanup unix n - n - 0 cleanup
qmgr fifo n - n 300 1 qmgr
#qmgr fifo n - n 300 1 oqmgr
tlsmgr unix - - n 1000? 1 tlsmgr
rewrite unix - - n - - trivial-rewrite
bounce unix - - n - 0 bounce
defer unix - - n - 0 bounce
trace unix - - n - 0 bounce
verify unix - - n - 1 verify
sacl-cache unix - - n - 1 sacl-cache
flush unix n - n 1000? 0 flush
proxymap unix - - n - - proxymap
# When relaying mail as backup MX, disable fallback_relay to avoid MX loops
relay unix - - n - - smtp
-o smtp_fallback_relay=
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
showq unix n - n - - showq
error unix - - n - - error
retry unix - - n - - error
discard unix - - n - - discard
local unix - n n - - local
virtual unix - n n - - virtual
lmtp unix - - n - - lmtp
anvil unix - - n - 1 anvil
scache unix - - n - 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/local/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=/usr/bin/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}
#
# ====================================================================
#
# Dovecot
#
dovecot unix - n n - 25 pipe
# flags=DRhu user=_dovecot:mail argv=/Applications/Server.app/Contents/ServerRoot/usr/libexec/dovecot/dovecot-lda -d ${user}
# Use these settings to enable +addressing ([email protected])
flags=DRhu user=_dovecot:mail argv=/Applications/Server.app/Contents/ServerRoot/usr/libexec/dovecot/dovecot-lda -d ${user} -a ${recipient} -m ${extension}
#
# ====================================================================
#
# Greylist policy server
#
policy unix - n n - - spawn
user=nobody:mail argv=/usr/bin/perl /usr/libexec/postfix/greylist.pl
#
# ====================================================================
#
# See the Postfix UUCP_README file for configuration details.
#
#uucp unix - n n - - pipe
# flags=Fqhu user=uucp argv=uux -r -n -z -a$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/local/sbin/bsmtp -f $sender $nexthop $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-amavis unix - - y - 2 smtp
-o smtp_data_done_timeout=1200
-o smtp_send_xforward_command=yes
-o disable_dns_lookups=yes
-o max_use=20
127.0.0.1:10025 inet n - y - - smtpd
-o content_filter=
-o smtpd_tls_security_level=none
-o smtpd_delay_reject=no
-o smtpd_client_restrictions=permit_mynetworks,reject
-o smtpd_helo_restrictions=
-o smtpd_sender_restrictions=
-o smtpd_recipient_restrictions=permit_mynetworks,reject
-o smtpd_data_restrictions=reject_unauth_pipelining
-o smtpd_end_of_data_restrictions=
-o smtpd_restriction_classes=
-o mynetworks=127.0.0.0/8
-o smtpd_error_sleep_time=0
-o smtpd_soft_error_limit=1001
-o smtpd_hard_error_limit=1000
-o smtpd_client_connection_count_limit=0
-o smtpd_client_connection_rate_limit=0
-o receive_override_options=no_header_body_checks,no_unknown_recipient_checks,no_milters
-o local_header_rewrite_clients=
-o smtpd_milters=
-o local_recipient_maps=
-o relay_recipient_maps=
编辑2：
经过进一步检查，当事情开始堵塞时，我仍然可以通过键入 telnet 到 10024 telnet 127.0.0.1 10024，但无法 telnet 到 10025。我收到以下错误：
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Can't assign requested address
Trying fe80::1...
telnet: connect to address fe80::1: Connection refused
telnet: Unable to connect to remote host
也许这会引出更多的线索？