利用msmtp命令查看邮件服务器支持的验证方式

[root@zabbix ~]# /usr/local/msmtp/bin/msmtp --host=smtp.qq.com --serverinfo
SMTP server at smtp.qq.com ([113.108.16.44]), port 25:
    smtp.qq.com Esmtp QQ Mail Server
Capabilities:
    SIZE 52428800:
        Maximum message size is 52428800 bytes = 50.00 MiB
    PIPELINING:
        Support for command grouping for faster transmission
    AUTH:
        Supported authentication methods:
        PLAIN LOGIN