12 Docker Tips to Save Disk Space, Limit Resources, and Secure Containers on Linux

A Docker host can run reliably for months and still fill its disk overnight or expose a port to your firewall that should have been blocked. These 12 practical tips use docker system prune, daemon.json, restart policies, and health checks to help prevent those problems.
Imagine receiving a disk-space alert from a server that has been running the same containers for months. Nothing new was deployed, yet /var/lib/docker has steadily grown because unused images, containers, volumes, and container logs were never cleaned up or rotate