似乎我可以 ping google DNS 到它的 IPv6 地址 2001:4860:4860::8888 但我不能 ping 它的 IPv4 地址 8.8.8.8
luka@luka-Inspiron-3458:~$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
^C
--- 8.8.8.8 ping statistics ---
173 packets transmitted, 0 received, 100% packet loss, time 173374ms
luka@luka-Inspiron-3458:~$ ping6 2001:4860:4860::8888
PING 2001:4860:4860::8888(2001:4860:4860::8888) 56 data bytes
64 bytes from 2001:4860:4860::8888: icmp_seq=1 ttl=48 time=286 ms
64 bytes from 2001:4860:4860::8888: icmp_seq=2 ttl=48 time=60.6 ms
64 bytes from 2001:4860:4860::8888: icmp_seq=3 ttl=48 time=61.3 ms
64 bytes from 2001:4860:4860::8888: icmp_seq=4 ttl=48 time=60.8 ms …