====== upstreamによるメールproxy ======

===== このページについて =====

[[serverapps:nginx:mailproxy|mailモジュールを使ったsmtp proxy]]に挫折したため、streamを利用してみます。



==== 注意 ====
※アプリケーション層より下でProxyされるため、Nginx側でSSLを設定できません。

===== Proxy側 =====
==== /usr/local/etc/nginx/nginx.conf ====
<code nginx>

stream {

    proxy_protocol on;

    #-- smtp ------------------------------------------
    upstream smtp {
        server SMTPSERVER:25;
    }
    server {
        listen          {ProxyIP}:25;
        error_log       /var/log/nginx/smtp-error.log error;
        proxy_pass      smtp;
    }
    #-- smtp isubmissionport----------------------------
    upstream smtp_submission {
        server SMTPSERVER:587;
    }
    server {
        listen          {ProxyIP}:587;
        error_log       /var/log/nginx/smtp-error.log error;
        proxy_pass      smtp_submission;
    }
    #-- imap ------------------------------------------
    upstream imap {
        server SMTPSERVER:143;
    }
    server {
        listen          {ProxyIP}:143;
        error_log       /var/log/nginx/imap-error.log error;
        proxy_pass      imap;
    }
    #-- pop3 ------------------------------------------
    upstream pop3 {
        server SMTPSERVER:110;
    }
    server {
        listen          {ProxyIP}:110;
        error_log       /var/log/nginx/pop3-error.log error;
        proxy_pass      pop3;
    }

}
</code>


===== メールサーバ側 =====

==== /usr/local/etc/postfix/main.cf ====

<code postfix>
smtpd_upstream_proxy_protocol = haproxy
</code>

==== /usr/local/etc/dovecot/local.conf ====

<code dovecot>
haproxy_trusted_networks = {Proxy IP}
</code>

==== /usr/local/etc/dovecot/conf.d/10-master.conf ====

<code dovecot>
service imap-login {
  inet_listener imap {
    #port = 143
    haproxy = yes
  }
}
service pop3-login {
  inet_listener pop3 {
    #port = 110
    haproxy = yes
  }
}
</code>

===== 参考 =====

[[https://www.nginx.com/resources/admin-guide/tcp-load-balancing/|NGINX LOAD BALANCING – TCP AND UDP LOAD BALANCER]]

[[https://tipstricks.itmatrix.eu/tcp-load-balancing-for-email-servers-with-nginx/|TCP Load balancing email/web servers with NginX]]

[[https://wiki2.dovecot.org/HAProxy|dovecot haproxy]]

[[http://www.postfix.org/postconf.5.html#smtpd_upstream_proxy_protocol| smtpd_upstream_proxy_protocol]]

[[http://tech.mercari.com/entry/2016/08/17/170114|nginxによるTCPロードバランサー]]