static #docker binary in #coreos

get-static-docker

#!/bin/bash

VERSION=$(docker --version | awk '{print $3}' | sed 's/,//')
BINARY="/opt/bin/docker-$VERSION-static"
LINK="/opt/bin/docker.static"

if [ ! -e "$BINARY" ]; then
    curl -L -o "$BINARY" "https://get.docker.com/builds/Linux/x86_64/docker-$VERSION"
    chmod a+x "$BINARY"
    ln -sf "$BINARY" "$LINK"
fi

static-docker.service

[Unit]
Description=Static docker downloader
Requires=docker.service
Before=docker.service

[Service]
Type=oneshot
ExecStart=/opt/bin/get-static-docker

[Install]
WantedBy=docker.service

@jfchevrette this is useful for cases where you want to use docker-in-docker, and be guaranteed that the inner one is compatible with the outer one (since docker basically doesn't have any useful notion of compatibility).

With this, you can just bind-mount the static docker binary, and you get those properties