haproxy配置如下：
global
log 127.0.0.1 local3 info
daemon
maxconn 1024
defaults
log global
mode tcp
option tcplog
timeout connect 10000
timeout client 240s
timeout server 240s
maxconn 20000
listen admin_stat
bind 0.0.0.0:8888
mode http
stats refresh 30s
stats uri /haproxy_stats
stats realm Haproxy\ statistics
stats auth admin:admin
stats hide-version
backend mqtt_backend
mode tcp
option tcplog
stick-table type string len 32 size 100k expire 30m
stick on req.payload(0,0),mqtt_field_value(connect,client_identifier)
balance roundrobin
server emqx1 127.0.0.1:1883 send-proxy-v2
frontend mqtt_servers
bind 0.0.0.0:1886
mode tcp
log global
option tcplog
tcp-request inspect-delay 10s
default_backend mqtt_backend
emqx配置如下：
listeners.tcp.default {
bind = “0.0.0.0:1883”
max_connections = 1024
proxy_protocol = true
}