★3.1Netcraft :子域名查询
官网:http://searchdns.netcraft.com/
输入要查询的域名,即可得知子域名
3.2Fierce :子域名查询
root@Kali:/home/dnt# fierce -dns cnblogs.com -threads 100 Trying zone transfer first... Unsuccessful in zone transfer (it was worth a shot) Okay, trying the good old fashioned way... brute force Checking for wildcard DNS... ** Found 99901599299.cnblogs.com at 42.121.252.58. ** High probability of wildcard DNS. Now performing 2280 test(s)... 120.26.70.206 files.cnblogs.com 42.121.129.234 images.cnblogs.com 223.6.251.45 group.cnblogs.com 223.6.251.45 home.cnblogs.com 42.121.129.234 download.cnblogs.com 221.181.200.235 cdn.cnblogs.com 42.121.131.85 mail.cnblogs.com 42.121.129.234 downloads.cnblogs.com 223.6.251.45 news.cnblogs.com 223.6.251.45 ad.cnblogs.com 42.121.254.229 p.cnblogs.com 。。。。。。。。