PCA (Prometheus Certified Associate) sample exam question with answer 388

Question:
What is required to be able to reload Prometheus via its /-/reload endpoint?

1. Send a SIGHUP to the Prometheus process
2. Set the --web.enable-lifecycle command line flag
3. Set the global attribute enable_reload: true in the Prometheus configuration file
4. Set the --web.enable-admin-api command line flag

Answer:
B - is the correct answer. More at reload
A - is incorrect. Though this will trigger a Prometheus reload, the question asks what is necessary to perform a reload via the /-/reload endpoint
C - there is no such attribute
D - is incorrect as the proper flag to set is --web.enable-lifecycle. The --web.enable-admin-api command line flag enables API endpoints for admin control actions while the --web.enable-lifecycle flag enables shutdown and reload via HTTP request