Docker & Kubernetes · Module 04

Docker Storage – Volumes, Bind Mounts and Storage Drivers

Understand why data inside a container is easy to lose, choose between volumes, bind mounts and tmpfs, manage volumes and know what a storage driver does.

Practice interactively →

What you will learn

• Explain the writable layer and when data inside a container is lost
• Choose a volume, bind mount or tmpfs and write it with -v or --mount
• Create, inspect, remove and prune Docker volumes safely
• Identify the storage driver in use and what it affects

Lessons

1. Data in a container and the writable layer

   Files written in a container live in a thin writable layer that disappears with the container on docker rm.

2. Three mount types — volume, bind mount, tmpfs

   Volumes are managed by Docker, bind mounts point at any host directory, tmpfs lives only in RAM.

3. Managing Docker volumes

   Create, inspect, share and clean up volumes; a volume outlives its containers until you remove it.

4. Storage drivers

   The storage driver stacks image layers and the writable layer on the host; overlay2 is the standard choice, and volumes bypass it.