haproxy.cfg

defaults
    mode http
    timeout connect 10s
    timeout client 1m
    timeout server 1m

frontend http_proxy_frontend
    bind *:7860
    
    http-request allow if METH_CONNECT

    default_backend external_proxies

backend external_proxies
    balance roundrobin
    
    server proxy1 216.26.235.213:3129 check
    server proxy2 65.111.12.148:3129 check
    server proxy3 216.26.230.8:3129 check