# Sendmail

Sendmail 是最早的互联网软件，也是早期Linux操作系统默认的邮件投递程序。在生产环境中，很多服务器会长期运行，保留了古老的操作系统，所以很可能还会遇到Sendmail问题需要处理。

本章节主要整理一些Sendmail异常排查的经验，不会系统部署和运维。

邮件系统的部署将采用比较现代的Postfix系统来实现。


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