Getting this?

haproxy-systemd-wrapper[17526]: [WARNING] 186/151058 (17527) : Setting tune.ssl.default-dh-param to 1024 by default, if your workload permits it you should set it to at least 2048. Please set a value >= 1024 to make this warning disappear.

add this to your haproxy config:

global
        log                     127.0.0.1       local3  warning
        pidfile                 /var/run/haproxy.pid
        maxconn                 4000
        user                    haproxy
        group                   haproxy
        daemon                  haproxy

        stats socket            /etc/haproxy/stats
        tune.ssl.default-dh-param 2048

Cheers,
TK