Hello,
on my forum I sometimes receive L7 DDoS attacks, which are filtered by a DDoS protection, but the first requests for new IPs get through.
This has the effect that PHP-FPM is overwhelmed by requests, and for a few minutes it stays processing these requests, while legitimate ones are answered by nginx with 504 Bad Gateway (immediately).
Questions for PHP experts:
1) what happens when 504 is returned? Which PHP-FPM limit makes this happen?
2) is there a way to make PHP stop procesing requests when the client connection is aborted (the DDoS clients are blocked at the firewall level when they're detected as such)?
Thanks!
