I've wasted most of my afternoon scouring the web for a solution to this. The closest I've found is this post https://geekflare.com/enable-jmx-tomcat-to-monitor-administer/ demonstrating the JMX setup, but using JConsole instead. The tab still doesn't work for me, but maybe you'll have better luck.

In searching this repo for the "Cluster information is only available with enabled cluster support." error message, I found the following under the changelog: MISC: Cluster support is disabled for Tomcat versions that do not export "Catalina:type=ClusterMembership" mbean. Being new to Tomcat, I'm coming up short on that one.

Seeing as how a proper setup isn't explained in the Wiki and previous questions here have been deflected, I'm beginning to wonder if it's ever been done. I've yet to find an image or video online displaying the contents of the Cluster tab. I've just resorted to using the status page (http://<apache_virtual_ip>/status) to see my cluster info.

When I took over on this project the message use to read cluster not supported with tomcat 5.5. Given many tomcat versions later that message made no sense so it was simply changed to be more generic. I've never setup a cluster myself so I suspect it has never worked except in really early rough days of tomcat psi probe and has never been revisited. If someone can through together a sample application with clustering enabeled that I can have for testing, I'd be more than happy to give this a look and see if support can be provided. That or any help with coding would be greatly appreciated.

The data for the cluster page is retrieved in ClusterWrapperBean. There the JMX beans used do not match the beans that Tomcat is exposing in latest versions. With some renaming and commenting it is possible to show some information about the cluster. Still I don't know how to get some of the info neither I know the meaning of most of this data.