Categories

Tools

Healthchecks and Restart Policies in Docker Compose

A healthcheck is a command Docker runs periodically inside the container to decide whether the service is healthy; its state moves from starting to healthy or unhealthy. Combined with a restart policy (no, always, on-failure or unless-stopped) and with depends_on and the service_healthy condition, it stops an application from starting before its database.

Architecture

Kubernetes 1.28: Sidecar Containers as First-Class Citizens

Kubernetes 1.28 introduces native sidecar containers in alpha via KEP-753: adding restartPolicy Always to initContainers ensures correct startup and shutdown ordering. It fixes Jobs that never terminate. Istio, Linkerd, and observability agents like Fluent Bit are the primary beneficiaries.