re:手工测试c:\>nslookup...
手工测试
c:\>nslookup
Default Server: fj_dns.test0.cn
Address: 218.85.157.99
> set type=mx
> ccc.com
Server: fj_dns.test0.cn
Address: 218.85.157.99
Non-authoritative answer:
ccc.com MX preference = 100, mail exchanger = echo.ccc.com
ccc.com MX preference = 10, mail exchanger = maxwell.ibp.com
ccc.com nameserver = bigjob.bicnet.net
ccc.com nameserver = namesrv.mdc.net
ccc.com nameserver = echo.ccc.com
maxwell.ibp.com internet address = 66.207.133.141
echo.ccc.com internet address = 198.137.187.6
bigjob.bicnet.net internet address = 209.251.64.254
namesrv.mdc.net internet address = 209.251.64.251
即可知道ccc.com有2个smtp接收服务器, 主服务器是maxwell.ibp.com, IP是66.207.133.141