i have deployed access manager 4.2 appliance after a tutorial.
the problem is , when i want to configure reverse proxy and click on cluster configuration > reverse proxy/authentication error is displayed :

description The server encountered an internal error that prevented it from fulfilling this request.


org.apache.jsp.jsp.volsc.config.ag.http.reverselis t_jsp._jspService(y:2603)
org.apache.jasper.runtime.HttpJspBase.service(Http JspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet .java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilt er(WsFilter.java:52)
com.volera.vcdn.webui.sc.core.WebApplicationFilter .doFilter(y:33)
note The full stack trace of the root cause is available in the Apache Tomcat logs.

can you please advise?
btw it's vm inside vmware , 8gb memory , 2vcpu