availability

Database redundancy still needs reconnecting clients. Distinguish the deployment type, then measure how promotion and DNS changes affect application requests.

Spreading instances across availability zones is not the same as surviving an AZ failure. What makes the difference is being able to name the four coupling points that quietly re-unify a blast radius you thought you had split.

Everyone can recite the three. Explain what each failure causes, and why a badly configured liveness probe is more dangerous than none at all.

PDB governs voluntary disruptions only and does not gate rolling updates at all. Describing it as 'it keeps N pods alive' states the part it does not do, since it constrains voluntary eviction and not the machine that fails.

Tests whether you know that Kubernetes waits, and for how long. The default timings surprise most candidates, and they explain why a node failure hurts longer than people expect.

Volumetric floods die at the anycast edge; everything else reaches your origin anyway. The origin leak, expensive endpoints and unproxied surfaces decide whether a CDN is armour or decoration.

The design round where the honest answer is mostly about data. Stateless traffic across regions is straightforward; the database is where active-active is either solved or pretended.