I'm trying to simulate a TCP SYN flood to tune a web server (planning to deploy on AWS).
I setup a 'target' VM, disabled iptables and running hping (hping -p 80 -i u1000 -c 1000 -S destaddr) from couple of local 'source' machines (filtering RST in OUTPUT chain of those).
I was expecting to see 1000 SYN_RECV records in netstat output of the target server, but I only see 256 max (256 per each 'source' machine). I seems hitting some limit on 'target' machine and can't find where it is. tcp_max_syn_backlog is increased to 8096.
Any idea where this limit is set?