possible SYN flooding on ctid 42131, port 80. Sending cookies. - Solution

The Linux Kernel interpretated a very high volume of real traffic as a DDOS attack so it basically ends up blocking your web server.

possible SYN flooding on ctid 42131, port 80. Sending cookies.

Simple fix edit sysctl values for max_syn_backlog
sysctl -w net.ipv4.tcp_max_syn_backlog=5000


To make them permanent edit /etc/sysctl.conf

echo "net.ipv4.tcp_max_syn_backlog=5000" >> /etc/sysctl.conf


Tags:

syn, flooding, ctid, solutionthe, linux, kernel, interpretated, volume, ddos, blocking, server, edit, sysctl, max_syn_backlog, ipv, tcp_max_syn_backlog, etc, conf, echo, quot,

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