1、

启动 sendmail 报错:Cannot exec /usr/sbin/sensible-mda: No such file or directory
解决:apt-get install sensible-mda
参考:http://readthefuckingmanual.net/error/231/

2、

sendmail 日志报错 stat=Deferred: Connection refused by [127.0.0.1] 且不能发送邮件
解决:修改 /etc/hosts 文件确保有这么一行:127.0.0.1 localhost.localdomain localhost