Spring Boot Monitoring with Actuator 3

Question 1

How can you add custom tags to every Micrometer metric emitted by your Spring Boot application?

Accepted Answer

Define a MeterRegistryCustomizer bean that calls registry.config().commonTags()

Answer

A MeterRegistryCustomizer bean lets you apply common tags globally to all meters registered in the application.

Question 2

What is the purpose of the /actuator/scheduledtasks endpoint?

Accepted Answer

Lists all @Scheduled methods, their configuration, and next execution time

Answer

The /actuator/scheduledtasks endpoint exposes metadata about all @Scheduled methods including cron expressions and fixed-rate settings.

Question 3

Which Actuator endpoint allows you to view and modify the logging level of a package at runtime?

Accepted Answer

/actuator/loggers

Answer

The /actuator/loggers endpoint supports GET to view and POST to dynamically change logger levels without restarting.

Question 4

Which HTTP method must you use to update a logger level via the /actuator/loggers endpoint?

Accepted Answer

POST

Answer

A POST request to /actuator/loggers/{name} with a JSON body like {"configuredLevel":"DEBUG"} updates the logger level.

Question 5

What does a DOWN status in /actuator/health indicate by default?

Accepted Answer

At least one HealthIndicator reported a DOWN status

Answer

The aggregate health is DOWN when any single registered HealthIndicator returns a DOWN status.

Spring Boot Practice Test