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NginX - Mitigating Slowloris Attack

Technically, NginX is not vulnerable to Slowloris attack. But the default configurations may not be able to handle Slowloris attack.

HEXADIX has published a how-to that is simple to follow:
https://hexadix.com/slowloris-dos-attack-mitigation-nginx-web-server/

The key steps are to increase the value of certain variables:

Under nginx.conf,
add the followings:

worker_rlimit_nofile 102400;

events {
worker_connections 100000;
}

Check the system and user open file limit.

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