一段 ping 命令的执行返回：

[[email protected] ~]# ping baidu.com PING baidu.com (220.181.38.148) 56(84) bytes of data. 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=1 ttl=49 time=35.9 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=2 ttl=49 time=67.4 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=3 ttl=49 time=37.6 ms ^C --- baidu.com ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2002ms rtt min/avg/max/mdev = 35.947/47.022/67.444/14.457 ms [[email protected] ~]# ping github.com PING github.com (13.229.188.59) 56(84) bytes of data. 64 bytes from ec2-13-229-188-59.ap-southeast-1.compute.amazonaws.com (13.229.188.59): icmp_seq=1 ttl=42 time=121 ms 64 bytes from ec2-13-229-188-59.ap-southeast-1.compute.amazonaws.com (13.229.188.59): icmp_seq=2 ttl=42 time=119 ms 64 bytes from ec2-13-229-188-59.ap-southeast-1.compute.amazonaws.com (13.229.188.59): icmp_seq=3 ttl=42 time=126 ms ^C --- github.com ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2003ms rtt min/avg/max/mdev = 119.436/122.369/126.585/3.069 ms [[email protected] ~]#  

疑问的是 ping github 的返回中 ec2-13-229-188-59.ap-southeast-1.compute.amazonaws.com 是拿来的，ping 返回的数据格式怎么理解？