docker-in-docker fails locally (works in codespaces)

[dsyer]

I have a fairly vanilla Ubuntu host which runs docker happily. When I start a devcontainer locally with docker-in-docker it fails. JSON:

{
	"name": "hello",
	"image": "mcr.microsoft.com/devcontainers/base:ubuntu",
	"remoteUser": "vscode",
	"features": {
		"ghcr.io/devcontainers/features/docker-in-docker:1": {}
	}
}

Error:

$ docker ps
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

The same JSON works in codespaces:

$ docker ps
CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES

[Chuxel]

This is now maintained out of devcontainers/features - raised devcontainers/features#285 there.