可以打开了
zss-Mac-Pro:~ zs$ ping tom.hu.tc
PING tom.hu.tc (208.43.223.205): 56 data bytes
64 bytes from 208.43.223.205: icmp_seq=0 ttl=47 time=279.592 ms
64 bytes from 208.43.223.205: icmp_seq=1 ttl=47 time=279.414 ms
64 bytes from 208.43.223.205: icmp_seq=2 ttl=47 time=279.159 ms
64 bytes from 208.43.223.205: icmp_seq=3 ttl=47 time=279.064 ms
64 bytes from 208.43.223.205: icmp_seq=4 ttl=47 time=278.937 ms
64 bytes from 208.43.223.205: icmp_seq=5 ttl=47 time=278.589 ms
64 bytes from 208.43.223.205: icmp_seq=6 ttl=47 time=278.468 ms