possible SYN flooding on port 80. Sending cookies. -

possible SYN flooding on port 80. Sending cookies.

Errors like this are shown on high usage servers and ports so it is common to see it on http and even imap ports:

possible SYN flooding on port 80. Sending cookies.

The Linux kernel will even detect flooding on OpenVZ containers:

possible SYN flooding on ctid 6000, port 993. Sending cookies.

In many cases this is not an issue and is more so simply a result of regular, but high usage traffic.


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