使用 iRedmail 安装程序成功安装邮件服务器后，我无法向外部网络发送电子邮件。
我可以成功接收邮件，但无法创建新邮件（发往外部网络）或回复已收到的邮件。
每当我发送电子邮件时，我的邮件日志中就会出现以下内容；
Jul 2 13:34:42 hostname postfix/smtp[113264]: connect to gmail-smtp-in.l.google.com[2a00:1450:4010:c03::1a]:25: Connection timed out
Jul 2 13:35:12 hostname postfix/smtp[113264]: connect to alt1.gmail-smtp-in.l.google.com[2404:6800:4003:c06::1a]:25: Connection timed out
和
1 Jul 1 13:29:46 hostname postfix/smtp[54364]: 49x3wF0hvGz2wtK: to=<[email protected]>, relay=none, delay=78302, delays=78241/0.04/60/0, dsn=4.4.1, status=deferred (connect to live-com.olc.protection.outlook.com[104.47.58.161]:25: Connection timed out)
我有
iRedMail 版本：1.3 Ubuntu：20.04 LTS
我检查了服务器“mbuyufikra.org”尚未被列入黑名单
还有 postfix main.cf 文件；
# --------------------
# INSTALL-TIME CONFIGURATION INFORMATION
#
# location of the Postfix queue. Default is /var/spool/postfix.
queue_directory = /var/spool/postfix
# location of all postXXX commands. Default is /usr/sbin.
command_directory = /usr/sbin
# location of all Postfix daemon programs (i.e. programs listed in the
# master.cf file). This directory must be owned by root.
# Default is /usr/libexec/postfix
daemon_directory = /usr/lib/postfix/sbin
# location of Postfix-writable data files (caches, random numbers).
# This directory must be owned by the mail_owner account (see below).
# Default is /var/lib/postfix.
data_directory = /var/lib/postfix
# owner of the Postfix queue and of most Postfix daemon processes.
# Specify the name of a user account THAT DOES NOT SHARE ITS USER OR GROUP ID
# WITH OTHER ACCOUNTS AND THAT OWNS NO OTHER FILES OR PROCESSES ON THE SYSTEM.
# In particular, don't specify nobody or daemon. PLEASE USE A DEDICATED USER.
# Default is postfix.
mail_owner = postfix
# The following parameters are used when installing a new Postfix version.
#
# sendmail_path: The full pathname of the Postfix sendmail command.
# This is the Sendmail-compatible mail posting interface.
#
sendmail_path = /usr/sbin/sendmail
# newaliases_path: The full pathname of the Postfix newaliases command.
# This is the Sendmail-compatible command to build alias databases.
#
newaliases_path = /usr/bin/newaliases
# full pathname of the Postfix mailq command. This is the Sendmail-compatible
# mail queue listing command.
mailq_path = /usr/bin/mailq
# group for mail submission and queue management commands.
# This must be a group name with a numerical group ID that is not shared with
# other accounts, not even with the Postfix account.
setgid_group = postdrop
# external command that is executed when a Postfix daemon program is run with
# the -D option.
#
# Use "command .. & sleep 5" so that the debugger can attach before
# the process marches on. If you use an X-based debugger, be sure to
# set up your XAUTHORITY environment variable before starting Postfix.
#
debugger_command =
PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
ddd $daemon_directory/$process_name $process_id & sleep 5
debug_peer_level = 2
# --------------------
# CUSTOM SETTINGS
#
# SMTP server response code when recipient or domain not found.
unknown_local_recipient_reject_code = 550
# Do not notify local user.
biff = no
# Disable the rewriting of "site!user" into "user@site".
swap_bangpath = no
# Disable the rewriting of the form "user%domain" to "user@domain".
allow_percent_hack = no
# Allow recipient address start with '-'.
allow_min_user = no
# Disable the SMTP VRFY command. This stops some techniques used to
# harvest email addresses.
disable_vrfy_command = yes
# Enable both IPv4 and/or IPv6: ipv4, ipv6, all.
inet_protocols = all
# Enable all network interfaces.
inet_interfaces = all
#
# TLS settings.
#
# SSL key, certificate, CA
#
smtpd_tls_key_file = /etc/ssl/private/iRedMail.key
smtpd_tls_cert_file = /etc/ssl/certs/iRedMail.crt
smtpd_tls_CAfile = /etc/ssl/certs/iRedMail.crt
smtpd_tls_CApath = /etc/ssl/certs
#
# Disable SSLv2, SSLv3
#
smtpd_tls_protocols = !SSLv2 !SSLv3
smtpd_tls_mandatory_protocols = !SSLv2 !SSLv3
smtp_tls_protocols = !SSLv2 !SSLv3
smtp_tls_mandatory_protocols = !SSLv2 !SSLv3
lmtp_tls_protocols = !SSLv2 !SSLv3
lmtp_tls_mandatory_protocols = !SSLv2 !SSLv3
#
# Fix 'The Logjam Attack'.
#
smtpd_tls_exclude_ciphers = aNULL, eNULL, EXPORT, DES, RC4, MD5, PSK, aECDH, EDH-DSS-DES-CBC3-SHA, EDH-RSA-DES-CDC3-SHA, KRB5-DE5, CBC3-SHA
smtpd_tls_dh512_param_file = /etc/ssl/dh512_param.pem
smtpd_tls_dh1024_param_file = /etc/ssl/dh2048_param.pem
tls_random_source = dev:/dev/urandom
# Log only a summary message on TLS handshake completion — no logging of client
# certificate trust-chain verification errors if client certificate
# verification is not required. With Postfix 2.8 and earlier, log the summary
# message, peer certificate summary information and unconditionally log
# trust-chain verification errors.
smtp_tls_loglevel = 1
smtpd_tls_loglevel = 1
# Opportunistic TLS: announce STARTTLS support to remote SMTP clients, but do
# not require that clients use TLS encryption.
smtpd_tls_security_level = may
# Produce `Received:` message headers that include information about the
# protocol and cipher used, as well as the remote SMTP client CommonName and
# client certificate issuer CommonName.
# This is disabled by default, as the information may be modified in transit
# through other mail servers. Only information that was recorded by the final
# destination can be trusted.
#smtpd_tls_received_header = yes
# Opportunistic TLS, used when Postfix sends email to remote SMTP server.
# Use TLS if this is supported by the remote SMTP server, otherwise use
# plaintext.
# References:
# - http://www.postfix.org/TLS_README.html#client_tls_may
# - http://www.postfix.org/postconf.5.html#smtp_tls_security_level
smtp_tls_security_level = may
# Use the same CA file as smtpd.
smtp_tls_CApath = /etc/ssl/certs
smtp_tls_CAfile = $smtpd_tls_CAfile
smtp_tls_note_starttls_offer = yes
# Enable long, non-repeating, queue IDs (queue file names).
# The benefit of non-repeating names is simpler logfile analysis and easier
# queue migration (there is no need to run "postsuper" to change queue file
# names that don't match their message file inode number).
enable_long_queue_ids = yes
# Reject unlisted sender and recipient
smtpd_reject_unlisted_recipient = yes
smtpd_reject_unlisted_sender = yes
# Header and body checks with PCRE table
header_checks = pcre:/etc/postfix/header_checks
body_checks = pcre:/etc/postfix/body_checks.pcre
# A mechanism to transform commands from remote SMTP clients.
# This is a last-resort tool to work around client commands that break
# interoperability with the Postfix SMTP server. Other uses involve fault
# injection to test Postfix's handling of invalid commands.
# Requires Postfix-2.7+.
smtpd_command_filter = pcre:/etc/postfix/command_filter.pcre
# HELO restriction
smtpd_helo_required = yes
smtpd_helo_restrictions =
permit_mynetworks
permit_sasl_authenticated
check_helo_access pcre:/etc/postfix/helo_access.pcre
reject_non_fqdn_helo_hostname
reject_unknown_helo_hostname
# Sender restrictions
smtpd_sender_restrictions =
reject_non_fqdn_sender
reject_unlisted_sender
permit_mynetworks
permit_sasl_authenticated
check_sender_access pcre:/etc/postfix/sender_access.pcre
reject_unknown_sender_domain
# Recipient restrictions
smtpd_recipient_restrictions =
reject_non_fqdn_recipient
reject_unlisted_recipient
check_policy_service inet:127.0.0.1:7777
permit_mynetworks
permit_sasl_authenticated
reject_unauth_destination
check_policy_service inet:127.0.0.1:12340
# END-OF-MESSAGE restrictions
smtpd_end_of_data_restrictions =
check_policy_service inet:127.0.0.1:7777
# Data restrictions
smtpd_data_restrictions = reject_unauth_pipelining
# SRS (Sender Rewriting Scheme) support
#sender_canonical_maps = tcp:127.0.0.1:7778
#sender_canonical_classes = envelope_sender
#recipient_canonical_maps = tcp:127.0.0.1:7779
#recipient_canonical_classes= envelope_recipient,header_recipient
proxy_read_maps = $canonical_maps $lmtp_generic_maps $local_recipient_maps $mydestination $mynetworks $recipient_bcc_maps $recipient_canonical_maps $relay_domains $relay_recipient_maps $relocated_maps $sender_bcc_maps $sender_canonical_maps $smtp_generic_maps $smtpd_sender_login_maps $transport_maps $virtual_alias_domains $virtual_alias_maps $virtual_mailbox_domains $virtual_mailbox_maps $smtpd_sender_restrictions $sender_dependent_relayhost_maps
# Avoid duplicate recipient messages. Default is 'yes'.
enable_original_recipient = no
# Virtual support.
virtual_minimum_uid = 2000
virtual_uid_maps = static:2000
virtual_gid_maps = static:2000
virtual_mailbox_base = /var/vmail
# Do not set virtual_alias_domains.
virtual_alias_domains =
#
# Enable SASL authentication on port 25 and force TLS-encrypted SASL authentication.
# WARNING: NOT RECOMMENDED to enable smtp auth on port 25, all end users should
# be forced to submit email through port 587 instead.
#
#smtpd_sasl_auth_enable = yes
#smtpd_sasl_security_options = noanonymous
#smtpd_tls_auth_only = yes
# hostname
myhostname = hostname.domain.org
myorigin = hostname.domain.org
mydomain = hostname.domain.org
# trusted SMTP clients which are allowed to relay mail through Postfix.
#
# Note: additional IP addresses/networks listed in mynetworks should be listed
# in iRedAPD setting 'MYNETWORKS' (in `/opt/iredapd/settings.py`) too.
# for example:
#
# MYNETWORKS = ['xx.xx.xx.xx', 'xx.xx.xx.0/24', ...]
#
mynetworks = 127.0.0.1 [::1]
# Accepted local emails
mydestination = $myhostname, localhost, localhost.localdomain
alias_maps = hash:/etc/postfix/aliases
alias_database = hash:/etc/postfix/aliases
# Default message_size_limit.
message_size_limit = 15728640
# The set of characters that can separate a user name from its extension
# (example: user+foo), or a .forward file name from its extension (example:
# .forward+foo).
# Postfix 2.11 and later supports multiple characters.
recipient_delimiter = +
# The time after which the sender receives a copy of the message headers of
# mail that is still queued. Default setting is disabled (0h) by Postfix.
#delay_warning_time = 1h
# Do not display the name of the recipient table in the "User unknown" responses.
# The extra detail makes trouble shooting easier but also reveals information
# that is nobody elses business.
show_user_unknown_table_name = no
compatibility_level = 2
#
# Lookup virtual mail accounts
#
transport_maps =
proxy:mysql:/etc/postfix/mysql/transport_maps_user.cf
proxy:mysql:/etc/postfix/mysql/transport_maps_maillist.cf
proxy:mysql:/etc/postfix/mysql/transport_maps_domain.cf
sender_dependent_relayhost_maps =
proxy:mysql:/etc/postfix/mysql/sender_dependent_relayhost_maps.cf
# Lookup table with the SASL login names that own the sender (MAIL FROM) addresses.
smtpd_sender_login_maps =
proxy:mysql:/etc/postfix/mysql/sender_login_maps.cf
virtual_mailbox_domains =
proxy:mysql:/etc/postfix/mysql/virtual_mailbox_domains.cf
relay_domains =
$mydestination
proxy:mysql:/etc/postfix/mysql/relay_domains.cf
virtual_mailbox_maps =
proxy:mysql:/etc/postfix/mysql/virtual_mailbox_maps.cf
virtual_alias_maps =
proxy:mysql:/etc/postfix/mysql/virtual_alias_maps.cf
proxy:mysql:/etc/postfix/mysql/domain_alias_maps.cf
proxy:mysql:/etc/postfix/mysql/catchall_maps.cf
proxy:mysql:/etc/postfix/mysql/domain_alias_catchall_maps.cf
sender_bcc_maps =
proxy:mysql:/etc/postfix/mysql/sender_bcc_maps_user.cf
proxy:mysql:/etc/postfix/mysql/sender_bcc_maps_domain.cf
recipient_bcc_maps =
proxy:mysql:/etc/postfix/mysql/recipient_bcc_maps_user.cf
proxy:mysql:/etc/postfix/mysql/recipient_bcc_maps_domain.cf
#
# Postscreen
#
postscreen_greet_action = drop
postscreen_blacklist_action = drop
postscreen_dnsbl_action = drop
postscreen_dnsbl_threshold = 2
# Attention:
# - zen.spamhaus.org free tire has 3 limits
# (https://www.spamhaus.org/organization/dnsblusage/):
#
# 1) Your use of the Spamhaus DNSBLs is non-commercial*, and
# 2) Your email traffic is less than 100,000 SMTP connections per day, and
# 3) Your DNSBL query volume is less than 300,000 queries per day.
#
# - FAQ: "Your DNSBL blocks nothing at all!"
# https://www.spamhaus.org/faq/section/DNSBL%20Usage#261
#
# It's strongly recommended to use a local DNS server for cache.
postscreen_dnsbl_sites =
zen.spamhaus.org=127.0.0.[2..11]*3
b.barracudacentral.org=127.0.0.2*2
postscreen_dnsbl_reply_map = texthash:/etc/postfix/postscreen_dnsbl_reply
postscreen_access_list = permit_mynetworks cidr:/etc/postfix/postscreen_access.cidr
# Require Postfix-2.11+
postscreen_dnsbl_whitelist_threshold = -2
#
# Dovecot SASL support.
#
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/dovecot-auth
virtual_transport = dovecot
dovecot_destination_recipient_limit = 1
#
# mlmmj - mailing list manager
#
mlmmj_destination_recipient_limit = 1
#
# Amavisd + SpamAssassin + ClamAV
#
content_filter = smtp-amavis:[127.0.0.1]:10024
# Concurrency per recipient limit.
smtp-amavis_destination_recipient_limit = 1
我根本没有触碰过这个文件，这只是 iRedmail 配置它的方式。