나는 눈치챘다 ping(아이틸스) id는 실행될 때마다 ICMP 카운터를 증가시킵니다. 나는 보려고 노력한다플랫 소스 코드주위를 둘러보았지만 카운터를 찾을 수 없었습니다. AFAIK ping은 데몬이나 기타 시스템 전역 상태를 실행하지 않으므로 Linux 커널 자체가 이 카운터에 대한 기록을 유지합니까?
% ping -c 3 127.0.0.1
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.039 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.039 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.033 ms
Tshark(ID=0x0043):
14267 196372.989831489 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) request id=0x0043, seq=1/256, ttl=64
14268 196372.989843064 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) reply id=0x0043, seq=1/256, ttl=64 (request in 14267)
14269 196374.001333266 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) request id=0x0043, seq=2/512, ttl=64
14270 196374.001345051 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) reply id=0x0043, seq=2/512, ttl=64 (request in 14269)
14271 196375.014707417 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) request id=0x0043, seq=3/768, ttl=64
14272 196375.014717838 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) reply id=0x0043, seq=3/768, ttl=64 (request in 14271)
다시 평평해짐:
% ping -c 3 127.0.0.1
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.047 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.062 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.037 ms
Tshark(ID=0x0044):
14273 196381.959906106 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) request id=0x0044, seq=1/256, ttl=64
14274 196381.959921324 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) reply id=0x0044, seq=1/256, ttl=64 (request in 14273)
14275 196382.961393309 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) request id=0x0044, seq=2/512, ttl=64
14276 196382.961404803 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) reply id=0x0044, seq=2/512, ttl=64 (request in 14275)
14277 196383.974709944 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) request id=0x0044, seq=3/768, ttl=64
14278 196383.974722217 127.0.0.1 → 127.0.0.1 ICMP 98 Echo (ping) reply id=0x0044, seq=3/768, ttl=64 (request in 14277)