命令:
nslookup -qt=MX tom.com
结果
Server: ns3.topway.cn
Address: 211.148.192.136
tom.com MX preference = 10, mail exchanger = tommx.163.net
tom.com nameserver = ns1.tom.com
tom.com nameserver = ns2.tom.com
tommx.163.net internet address = 202.108.252.141
tommx.163.net internet address = 202.108.255.210
ns1.tom.com internet address = 61.135.159.46
ns2.tom.com internet address = 61.135.159.47
我觉得你应该从DNS协议入手,今天好困,不帮你细研究了