参考网址:http://www.zytrax.com/books/dns/ch9/spf.htmlRFC-4408:http://www.zytrax.com/books/dns/apd/rfc4408.txtSPF的作用:Most domains send outbound mail through a relatively small number of servers. Domains should describe that set of servers in an SPF record in their DNS. Internet email receivers can then reject forged messages which don't come from an envelope sender domain's approved servers.许多域名向外发邮件时,会通过多个相关服务器来发送。域名必须在它的DNS里面定义SPF来规定这一组服务器。如果邮件发送来源不属于SPF规定的服务器,邮件接收者可以拒绝这种虚假的邮件。SPF怎么做:为zgsj邮箱的域名添加TXT记录时,主机名为空,TXT记录值为:"v=spf1 include:zgsj.com -all" (不包含引号)SPF语法:参考:http://www.openspf.org/SPF_Record_Syntax指令:all | ip4 | ip6 | a | mx | ptr | exists | includeAll-----------------------------------------+all 所有的IP都允许发送。-all 除了匹配的IP,其他都不允许发送,否则就是冒名.硬失败?all 除了匹配的IP,其他的你们自己的策略决定是否拦截。中立~all 除了匹配的IP,其他的IP算软失败。