containerd image store with Docker Engine

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The containerd image store is an experimental feature of Docker Engine. If you're using Docker Desktop, refer to the instructions on the containerd image store with Docker Desktop page.

containerd, the industry-standard container runtime, uses snapshotters instead of the classic storage drivers for storing image and container data. While the overlay2 driver still remains the default driver for Docker Engine, you can opt in to using containerd snapshotters as an experimental feature.

To learn more about the containerd image store and its benefits, refer to containerd image store on Docker Desktop.

Enable containerd image store on Docker Engine

Switching to containerd snapshotters causes you to temporarily lose images and containers created using the classic storage drivers. Those resources still exist on your filesystem, and you can retrieve them by turning off the containerd snapshotters feature.

The following steps explain how to enable the containerd snapshotters feature.

1. Add the following configuration to your /etc/docker/daemon.json configuration file:

   {
     "features": {
       "containerd-snapshotter": true
     }
   }

2. Save the file.

3. Restart the daemon for the changes to take effect.

   $ sudo systemctl restart docker
   

After restarting the daemon, running docker info shows that you're using containerd snapshotter storage drivers.

$ docker info -f '{{ .DriverStatus }}'
[[driver-type io.containerd.snapshotter.v1]]

Docker Engine uses the overlayfs containerd snapshotter by default.