Prevent short connections from draining your dynamic TCP port

See TCP protocol
Https://en.wikipedia.org/wiki/Transmission_Control_Protocol

But time_wait is a time window, and Linux defaults to 60 seconds.
Therefore, if the TCP session is generated and closed continuously, it can cause the problem mentioned earlier.


For Linux clients, this problem can be solved by adjusting several operating system kernel parameters.

net.ipv4.tcp_syncookies=1   # 开启SYN Cookies。当出现SYN等待队列溢出时，启用cookie来处理，可防范少量的SYN攻击net.ipv4.tcp_tw_recycle=1   # 开启TCP连接中TIME-WAIT套接字的快速回收net.ipv4.tcp_tw_reuse=1 # 开启重用。允许将TIME-WAIT套接字重新用于新的TCP连接net.ipv4.tcp_timestamps=1 # 减少time_waitnet.ipv4.tcp_tw_timeout=3 # 收缩TIME_WAIT状态socket的回收时间窗口

Prevent short connections from draining your dynamic TCP port