I wanted to build a proxy server with HAProxy to run multiple Minecraft servers, but it didn't work.
There seems to be a way to do it with BungeeCord, but I want to do it using a proxy.

What I want to do is to access the server at port 55555 when I access mc.example.com on the Minecraft side.
The port of 25565 is open, and the port of 55555 is not open on either the router side or the server side.
I also executedsystemctl restart haproxyfirmly

OS: CentOS 7.7.1908

frontend minecraft
    bind *: 25565
    mode tcp
    option tcplog
    balance roundrobin
    use_backend _55555 if {hdr (host) -m sub mc}
backend _55555
    tcp-request content accept
    server 55555

Please tell us if the necessary information is missing.