ping 응답을 비활성화하기 위해 다음을 실행 한 후 :
# sysctl net.ipv4.icmp_echo_ignore_all=1
# sysctl -p
ping ping localhost와 127.0.0.1에서 다른 결과를 얻습니다.
# ping -c 3 localhost
PING localhost(localhost (::1)) 56 data bytes
64 bytes from localhost (::1): icmp_seq=1 ttl=64 time=0.029 ms
64 bytes from localhost (::1): icmp_seq=2 ttl=64 time=0.035 ms
64 bytes from localhost (::1): icmp_seq=3 ttl=64 time=0.101 ms
--- localhost ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2042ms
rtt min/avg/max/mdev = 0.047/0.072/0.101/0.022 ms
핑 127.0.0.1 실패 :
ping -c 3 127.0.0.1
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
--- 127.0.0.1 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2032ms
이 결과가 다른 이유는 무엇입니까?