Managing configuration and secrets in Kubernetes is a critical DevOps responsibility that directly impacts security and reliability. This guide clarifies a fundamental misconception: Kubernetes injects configuration data but does not manage its lifecycle or automatic reloading. A core distinction exists between ConfigMaps, used for non-sensitive data like URLs and flags, and Secrets, which handle credentials and tokens.

While Secrets are base64 encoded, they are not encrypted by default and require RBAC controls and encryption at rest to prevent data leaks. The article details three injection methods: environment variables (requiring pod restarts), bulk envFrom injection, and the preferred method of mounting files, which supports live reloading if the application is coded to watch for file changes. A common production pitfall is updating a ConfigMap without triggering a rolling restart of the associated pods, leading to configuration drift and unexpected application behavior.

To mitigate this, senior DevOps engineers utilize hash-based annotations to force redeployments or integrate external secret managers like HashiCorp Vault for rotation and audit trails.