我有一个VPS的Ubuntu 10.04，安装和设置一个单一的系统用户的Postfix和Dovecot遵循这个和本指南。 我可以发送电子邮件，但不能接收它们。 我有一个域tema.ee，它有所有必要的DNSlogging
tema@artemis:~$ host tema.ee tema.ee has address 46.182.27.240 tema.ee mail is handled by 10 tema.ee. tema@artemis:~$ host -t NS tema.ee tema.ee name server ns2.selectel.org. tema.ee name server ns1.selectel.org. 除了imaplogin和断开连接消息之外，当我收到电子邮件时，/ /var/log/mail.log中没有任何内容。
主机文件：
tema@artemis:~$ sudo cat /etc/hosts 127.0.0.1 localhost 46.182.27.240 tema.ee artemis
主机名：
tema@artemis:~$ hostname -f tema.ee
Netstat输出：
tema@artemis:~$ netstat -tap Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 *:imap2 *:* LISTEN - tcp 0 0 *:sunrpc *:* LISTEN - tcp 0 0 *:36243 *:* LISTEN - tcp 0 0 *:ssh *:* LISTEN - tcp 0 0 *:imaps *:* LISTEN - tcp 0 0 *:2025 *:* LISTEN - tcp 0 48 tema.ee:ssh 89-235-215-24.sat:62504 ESTABLISHED - tcp 0 0 tema.ee:imaps 89-235-215-24.sat:63988 ESTABLISHED - tcp 0 0 tema.ee:imaps 89-235-215-24.sat:63992 ESTABLISHED - tcp6 0 0 [::]:ssh [::]:* LISTEN - tcp6 0 0 [::]:2025 [::]:* LISTEN -
这是我的main.cf为后缀：
smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) biff = no append_dot_mydomain = no #delay_warning_time = 4h readme_directory = no # TLS parameters smtpd_tls_cert_file = /etc/ssl/certs/smtpd.crt smtpd_tls_key_file = /etc/ssl/private/smtpd.key smtpd_use_tls=yes smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache myhostname = tema.ee alias_maps = hash:/etc/aliases alias_database = hash:/etc/aliases myorigin = /etc/mailname mydestination = tema.ee, localhost, artemis 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 home_mailbox = Maildir/ mailbox_command = smtpd_sasl_local_domain = smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous broken_sasl_auth_clients = yes smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination smtp_tls_security_level = may smtpd_tls_security_level = may smtpd_tls_auth_only = no smtp_tls_note_starttls_offer = yes smtpd_tls_CAfile = /etc/ssl/certs/cacert.pem smtpd_tls_loglevel = 1 smtpd_tls_received_header = yes smtpd_tls_session_cache_timeout = 3600s tls_random_source = dev:/dev/urandom
实际上，起初我以为有一些与DNS有关的事情，但我已经build立了另一个域（来自不同的注册商）的第二个虚拟机，做了相同的configuration，得到了相同的结果 – 我可以发送，但不能接收邮件。 可能是什么问题呢？
有一个防火墙问题。
您的主机在端口25上不可用
% nc 46.182.27.240 25 (UNKNOWN) [46.182.27.240] 25 (smtp) : No route to host
看（或显示我们）的输出
iptables-save