The HAProxy Stats is a great and powerful page. It provides a few abilities:
The HAProxy Stats page gives you a near real-time feed of information that you can use to troubleshoot proxied services, get insights about your traffic, and watch the load placed upon your servers. However, the metrics are labelled using shorthand names and prefixes.
Also the HAProxy Stats page grant ability to manage frontends/backends.
If HAProxy service has been installed not via HAProxy-WI, should be checked HAProxy Stats page. If the "listen stats" exists, you should configure HAProxy-WI for working with your configuration.
Go to the Servers -> Settings. Edit settings inside the "haproxy section" according to your listen stats configuration(in the black box)
If HAProxy service has been installed not via HAProxy-WI, should be checked HAProxy Stats page. If the "listen stats" does not exist, you should configure HAProxy service for working with HAProxy-WI.
How to do it you may figure out in this article