Spring profiles: active profile not loaded because name is misspelled

Defining a profile in application-prod.yml but activating spring.profiles.active=production causes Spring to load application.yml only; the prod file is silently ignored because the names do not match exactly.

The filename suffix must match the profile name character-for-character:

application-prod.yml     -> spring.profiles.active=prod
application-production.yml -> spring.profiles.active=production

Verify active profiles on startup — Spring logs them at INFO level:

The following 1 profile is active: "prod"

For multi-profile files in a single YAML document, use the --- separator with spring.config.activate.on-profile:

spring:
  datasource:
    url: jdbc:h2:mem:testdb
---
spring:
  config:
    activate:
      on-profile: prod
  datasource:
    url: jdbc:postgresql://prod-host/mydb

Spring's PropertySourceLoader resolves profile-specific files by appending the active profile name to the base filename. A mismatch produces no error; the file simply does not match the pattern and is not loaded.