Persistent Storage with Volumes

Containers are ephemeral by default — when a container is removed, its writable layer is deleted. For databases, uploads, configuration, and logs, you need persistent storage. This lesson covers volumes, bind mounts, tmpfs, volume management, backup strategies, and data sharing.

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Why Persistent Storage Matters

Without volumes:                    With volumes:
+-----------+                       +-----------+
| Container | -- rm --> Data LOST   | Container | -- rm --> Data SAFE
| + data    |                       |   |       |           in volume
+-----------+                       +---+-------+
                                        |
                                   +----v----+
                                   |  Volume  |
                                   +---------+

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Storage Options Compared

Docker offers three types of storage mounts:

Type	Stored Where	Managed By	Performance	Use Case
Volume	Docker-managed area on host	Docker	Best	Databases, persistent data
Bind mount	Specific host path	You	Good	Development, config files
tmpfs	Host memory only	Docker	Fastest	Secrets, temp data

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Volumes

Volumes are the recommended way to persist data in Docker. They are managed by Docker and stored in a dedicated area on the host filesystem.

Creating and Using Volumes