In the SRE hierarchy of service needs, which capability sits at the base, so that incident response, postmortems, and capacity planning all depend on it?
Show answer and explanation
Answer: C
Monitoring and observability form the foundation of the SRE hierarchy. Without reliable signals about latency, errors, and saturation, a team cannot tell that something is wrong, cannot respond to incidents, and cannot learn from them. Higher layers such as incident response, postmortems, testing and release, and capacity planning all assume good telemetry already exists. The ordering works like Maslow's hierarchy: a team should not invest in later layers while the base is missing.
Why the other options are wrong
- A. Postmortems sit above the foundation. They analyze incidents, which requires that monitoring detected the incident in the first place, so they depend on the base layer rather than forming it.
- B. Capacity planning is a higher layer that forecasts future demand. Good forecasts rely on accurate historical telemetry, so this capability is built on top of monitoring rather than beneath it.
- D. Developer productivity sits near the top of the hierarchy. Its improvements are only measurable and sustainable once the system's health is visible, so it is not the base capability.