[akira@dev001]$ ping -c 10 128.199.***.***
PING 128.199.***.*** (128.199.***.***) 56(84) bytes of data.
64 bytes from 128.199.***.***: icmp_seq=1 ttl=53 time=76.7 ms
64 bytes from 128.199.***.***: icmp_seq=2 ttl=53 time=75.7 ms
64 bytes from 128.199.***.***: icmp_seq=3 ttl=53 time=73.8 ms
64 bytes from 128.199.***.***: icmp_seq=4 ttl=53 time=73.7 ms
64 bytes from 128.199.***.***: icmp_seq=5 ttl=53 time=74.1 ms
64 bytes from 128.199.***.***: icmp_seq=6 ttl=53 time=76.1 ms
64 bytes from 128.199.***.***: icmp_seq=7 ttl=53 time=75.8 ms
64 bytes from 128.199.***.***: icmp_seq=8 ttl=53 time=75.7 ms
64 bytes from 128.199.***.***: icmp_seq=9 ttl=53 time=76.1 ms
64 bytes from 128.199.***.***: icmp_seq=10 ttl=53 time=78.0 ms
--- 128.199.***.*** ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 9096ms
rtt min/avg/max/mdev = 73.738/75.623/78.060/1.290 ms
dmesgには下記が延々と出続けている。possible SYN flooding on port 24224はtd-agentがポート開いてるけどaccept(2)してないから出ていると@hiboma先生がサクッと検証用のコードを書いて調査してくれた。
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possible SYN flooding on port 24224. Sending cookies.
possible SYN flooding on port 24224. Sending cookies.
possible SYN flooding on port 24224. Sending cookies.