Hello Federico @grumvalski I tried before use `haproxy` protocol and found Kamailio implementation is very restrictive.
As example 1) CPU 100% usage when created TCP connection and data do not send #2658 2) no ability to define a list of trusted sources, because now any fraud host can send crafted haproxy packet and break ACL rules used on Kamailio side. Relevant feature `set_real_ip_from` exist in nginx ([Link](https://nginx.org/en/docs/http/ngx_http_realip_module.html#set_real_ip_from)). From my point of view it is a big security hole.
Could you also look for limitations described above.
Just for info, nginx config snippet with haproxy feature. ``` server { listen 0.0.0.0:3128 proxy_protocol; listen [::]:3128 proxy_protocol; set_real_ip_from 4.101.84.5/32; set_real_ip_from 4.101.84.133/32; set_real_ip_from 4.236.25.5/32; set_real_ip_from 4.236.25.133/32; real_ip_header proxy_protocol; ... ```