intermediate

ConfigMap

Store non-secret configuration separately from images so workloads can be configured by environment.

A ConfigMap stores non-secret configuration separately from the image so the same artifact can run in different environments via env vars or mounted files.

					apiVersion: v1
kind: ConfigMap
metadata:
  name: api-config
data:
  LOG_LEVEL: info
  FEATURE_BETA: "false"
---
envFrom:
  - configMapRef:
      name: api-config

Environment variables from ConfigMaps are snapshots at pod start. Mounted files can be updated, but apps must reload or pods must restart.

On interviews: reload behavior, env vs volume mounts, immutable ConfigMaps, and why secrets belong elsewhere.

Common pitfalls: expecting hot reload without app support; storing credentials in ConfigMaps.

The trade-off is simple config injection versus operational steps to roll out config changes.

Checklist:

ConfigMaps only for non-secrets.
Plan reload or controlled rollout.
Version important config changes.
Keep image environment-agnostic.