The Discovery Registration Tool
To make themselves discoverable through the Discovery Endpoint, the various microservices of a Content Delivery environment must register themselves with the Discovery Service as Capabilities. You can do this by configuring the microservice to automatically register itself, or you can use a Java tool called the Discovery Registration Tool to perform the registration manually.
A Content Delivery environment has a number of different features it can expose to clients and APIs in the form of microservices. In the context of the Discovery Service, these features are referred to as Capabilities. Through the Discovery Endpoint, a client can discover if a certain feature is present on the Content Delivery environment, and if so, where the client can access its endpoint(s).
To make this work, each Content Delivery microservice must register itself with the Discovery Service. You can do this in multiple ways:
On the one hand, you can run the installation script for the feature (either installService.ps1, start.ps1 or start.sh) with the switch --auto-register. This automatically registers your microservice with the Discovery Service.
java -jar discovery-registration.jar update
Either of these two methods updates the Discovery Service database, making the information available to the Discovery Service automatically (no restart of the Discovery Service is required).
java -jar discovery-registration.jar read
java -jar discovery-registration.jar sync
This updates all registered Capabilities that are listed in cd_storage_conf.xml, and removes all registered Capabilities that are not listed in cd_storage_conf.xml. (To stop the tool from prompting you to confirm the removal of Capabilities, replace sync with forceSync.)