Every instance in a fleet must always have the CloudWatch agent installed and running, and the configuration must be reapplied whenever someone removes it. Which Systems Manager feature fits best?
Show answer and explanation
Answer: A
State Manager uses associations that bind a document to a target set and apply it on a schedule. Because the association keeps running, a package that is uninstalled or a service that is stopped is noticed and corrected at the next interval.
That ongoing enforcement of a desired configuration is what separates it from a one-off remote execution.
Why the other options are wrong
- B. Run Command sends a command and returns the output, but nothing re-checks the target afterward, so a later removal goes unnoticed.
- C. Session Manager provides interactive shell access to instances and does not enforce configuration state.
- D. Patch Manager handles operating system and application patching against a baseline, not general desired-state enforcement.
Exam tip. State Manager equals recurring desired state; Run Command equals fire once.