如何将后缀端口从25更改为587？

我对Unix和CLI完全陌生。谷歌搜索了将近6个小时之后，我知道我应该将postfix端口从25修改为587，以使PHP mail（）函数正常工作。这是我得到的解决方案http://www.linuxmail.info/postfix-change-port/，但是我不确定如何更改它。如前所述，我是菜鸟。任何帮助，将不胜感激。

UPDATE1：

grawity解决方案给了我以下错误。

May  7 00:42:39 Ibrahim-Armars-MacBook-Pro postfix/pickup[4169]: DE2073F07C1: uid=501 from=<azhararmar>
May  7 00:42:39 Ibrahim-Armars-MacBook-Pro postfix/master[4185]: fatal: open lock file pid/master.pid: unable to set exclusive lock: Resource temporarily unavailable
May  7 00:42:39 Ibrahim-Armars-MacBook-Pro postfix/cleanup[4177]: DE2073F07C1: message-id=<20110506191239.DE2073F07C1@Ibrahim-Armars-MacBook-Pro.local>
May  7 00:42:39 Ibrahim-Armars-MacBook-Pro postfix/qmgr[4168]: DE2073F07C1: from=<azhararmar@Ibrahim-Armars-MacBook-Pro.local>, size=525, nrcpt=1 (queue active)
May  7 00:42:40 Ibrahim-Armars-MacBook-Pro postfix/smtp[4179]: DE2073F07C1: to=<azhar@iarmar.com>, relay=smtp.gmail.com[74.125.155.109]:587, delay=0.8, delays=0.01/0/0.79/0, dsn=4.7.5, status=deferred (TLS is required, but our TLS engine is unavailable)
May  7 00:42:41 Ibrahim-Armars-MacBook-Pro postfix/pickup[4169]: 5F2FC3F07C4: uid=501 from=<azhararmar>
May  7 00:42:41 Ibrahim-Armars-MacBook-Pro postfix/cleanup[4177]: 5F2FC3F07C4: message-id=<20110506191241.5F2FC3F07C4@Ibrahim-Armars-MacBook-Pro.local>
May  7 00:42:41 Ibrahim-Armars-MacBook-Pro postfix/qmgr[4168]: 5F2FC3F07C4: from=<azhararmar@Ibrahim-Armars-MacBook-Pro.local>, size=525, nrcpt=1 (queue active)
May  7 00:42:42 Ibrahim-Armars-MacBook-Pro postfix/smtp[4179]: 5F2FC3F07C4: to=<azhar@iarmar.com>, relay=smtp.gmail.com[74.125.155.109]:587, delay=0.79, delays=0.01/0/0.78/0, dsn=4.7.5, status=deferred (TLS is required, but our TLS engine is unavailable)
May  7 00:42:50 Ibrahim-Armars-MacBook-Pro postfix/master[4190]: fatal: open lock file pid/master.pid: unable to set exclusive lock: Resource temporarily unavailable

更新2：

May  7 01:10:02 Ibrahim-Armars-MacBook-Pro postfix/master[4472]: fatal: open lock file pid/master.pid: unable to set exclusive lock: Resource temporarily unavailable
May  7 01:10:02 Ibrahim-Armars-MacBook-Pro postfix/pickup[4419]: 357F73F090F: uid=501 from=<azhararmar>
May  7 01:10:02 Ibrahim-Armars-MacBook-Pro postfix/cleanup[4430]: 357F73F090F: message-id=<20110506194002.357F73F090F@Ibrahim-Armars-MacBook-Pro.local>
May  7 01:10:02 Ibrahim-Armars-MacBook-Pro postfix/qmgr[4420]: 357F73F090F: from=<azhararmar@Ibrahim-Armars-MacBook-Pro.local>, size=525, nrcpt=1 (queue active)
May  7 01:10:03 Ibrahim-Armars-MacBook-Pro postfix/smtp[4448]: certificate verification failed for smtp.gmail.com[74.125.155.109]:587: untrusted issuer /C=US/O=Equifax/OU=Equifax Secure Certificate Authority

根据您对其他答案的评论，您需要配置Postfix以将Gmail用作中继主机。互联网上有很多关于此的教程；这是一个快速版本。

注意：使用此配置，所有邮件都必须使用您的Gmail地址作为“发件人”发送。

1. 撤消对的所有更改master.cf。

2. 在中main.cf，添加以下设置：

   # This tells Postfix to hand off all messages to Gmail, and never do direct delivery.
   relayhost = [smtp.gmail.com]:587
   
   # This enables TLS (SMTPS) certificate verification, because Gmail has a valid one.
   smtp_tls_security_level = verify
   smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt
   smtp_tls_session_cache_database = btree:/var/run/smtp_tls_session_cache
   
   # This tells Postfix to provide the username/password when Gmail asks for one.
   smtp_sasl_auth_enable = yes
   smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
   smtp_sasl_security_options = noanonymous
   

3. 在中/etc/postfix/sasl_passwd，添加您的Gmail用户名和密码，如下所示：

   [smtp.gmail.com]:587    user@gmail.com:mypassword
   

4. 将sasl_passwd文件编译到数据库中：

   postmap /etc/postfix/sasl_passwd
   

5. 最后重新加载Postfix的主要配置：

   postfix reload
   

如果您只希望它在端口587上运行（我不确定您是否愿意；我想您希望它同时在25 和 587 上运行），那么请在/etc/postfix/master.cf中找到该行看起来像这样：

smtp      inet  n       -       n       -       -       smtpd

并将其更改为如下所示：

587      inet  n       -       n       -       -       smtpd

如果您希望它同时在两个端口上运行，则在第一行之后添加第二行，而不是替换它。