docker-data-move.sh

中文说明 / README.zh.md

An interactive helper for moving Docker's data-root to a larger disk safely.

It builds on the original docker-data-move.sh idea, but adds:

• automatic detection of the current Docker data directory
• automatic disk scanning and free-space comparison
• recommended target paths sorted by available space
• interactive selection or --auto mode
• safer pre-checks for free space, path nesting, and daemon.json
• backup of the old Docker data directory and Docker config

Why this exists

A common production problem looks like this:

• /home or /var is full
• Docker overlay layers live under the full filesystem
• another mount such as /data still has hundreds of GB free

This script helps you move Docker data to the larger mount with less manual work.

What it does

1. Detects Docker's current data-root
2. Calculates how much free space the migration target should have
3. Scans local filesystems and suggests the best candidate paths
4. Lets you choose a suggested path or enter a custom path
5. Stops Docker and containerd
6. Copies Docker data with rsync
7. Updates /etc/docker/daemon.json
8. Restarts Docker
9. Verifies the new Docker Root Dir

Usage

Interactive mode:

sudo ./docker-data-move.sh

Specify a target path directly:

sudo ./docker-data-move.sh --path /data/docker-data

Auto-pick the best detected path:

sudo ./docker-data-move.sh --auto

Skip confirmation prompts:

sudo ./docker-data-move.sh --auto --yes

Allow using a non-empty target directory:

sudo ALLOW_NONEMPTY=1 ./docker-data-move.sh --path /data/docker-data

Example

If your machine looks like:

/home   100% used
/data   plenty of free space

the script will typically recommend a target like:

/data/docker-data

Requirements

• Linux
• Docker installed
• rsync available
• root privileges

Optional:

• jq for safer JSON updates to /etc/docker/daemon.json

Notes

• The script avoids recommending the same filesystem that currently stores Docker data.
• It keeps a backup of the old Docker data directory as ...bak.TIMESTAMP.
• If daemon.json already exists, it is backed up before modification.

Suggested verification after migration

docker info | grep "Docker Root Dir"
docker ps
df -h

Repository

• GitHub: tool-tl/docker-data-move.sh