What port do the Dynatrace Managed UI, OneAgent, and REST API use to communicate with the cluster?

The correct choice is 443 because it is the standard port used for secure HTTPS communication. In the context of Dynatrace Managed components, this port is essential for ensuring encrypted and secure interactions between the Dynatrace Managed UI, OneAgent, and REST API with the cluster. The use of port 443 allows for secure data transmission, which is critical for maintaining the confidentiality and integrity of the monitoring data exchanged between these components and the Dynatrace environment.

Other common ports such as 8080, 9999, and 8443 may serve specific purposes in various applications or configurations, but they are not the default for secure communications in Dynatrace Managed environments. Port 8080 is typically used for unsecured HTTP traffic, while 9999 and 8443 can be designated for alternative services or configurations, which are not standard for Dynatrace's communication requirements. Therefore, understanding the significance of port 443 is key for anyone working with Dynatrace Managed environments to ensure proper setup and communication across components.