While trying to enable the End User Experience in the Controller, it returns an error similar to the following:
EUM license usage retrieval failed (Error fetching license usage information [org.apache.http.conn.HttpHostConnectException
For example, in an environment using the AppDynamics SaaS EUM the full error might read:
EUM license usage retrieval failed (Error fetching license usage information [org.apache.http.conn.HttpHostConnectException: Connect to agg.eum-appdynamics.com:443 [agg.eum-appdynamics.com/184.108.40.206, agg.eum-appdynamics.com/220.127.116.11, agg.eum-appdynamics.com/18.104.22.168, agg.eum-appdynamics.com/22.214.171.124, agg.eum-appdynamics.com/126.96.36.199, agg.eum-appdynamics.com/188.8.131.52] failed: Connection refused while calling 'https://agg.eum-appdynamics.com/eumaggregator/licenseUsage'])
To use EUM, you must have port 443 open on the Controller machine so the Controller can access the EUM cloud to collect EUM metrics. The EUM cloud can be the AppDynamics Cloud or your own if you have set up an on-premise EUM Server.
For EUM in AppDynamics Cloud Environment
The Controller needs to access agg.eum-appdynamics.com through internet using HTTP over SSL on port :443.
For On-Premises EUM
the URL agg.eum-appdynamics.com will be different, but the issue is the same. Make sure port 443 is open.
Confirm that port 443 is open and is not blocked by a firewall.