可能重复: -如何正确配置SMTP传递反向FAIL: Found reverse DNS entries which don't resolves
IP-IP-IP-IP.HOST.DOMAIN.TLDAll IP's reverse DNS entries should resolve back to IP address (MX record's name -> IP -> IP ReverseMany mail servers a
ping -a 192.168.99.3不解析vcl.nailit.lab的主机名,而是解析网络上的其他主机(如pfsense.nailit.lab )。), Minimum = 0ms, Maximum = 0ms, Average = 0ms**ping -a到底是如何解析主机名的?为什么除了'ping -a 192.168.99.3‘以外的所