How do I create an external volume using docker compose? - docker

Question

Basing on this Node-RED tutorial, I'm trying to mount an external volume with the Node-RED files outside the docker machine. I'm using the following docker-compose file:
version: "3.7"
services:
node-red:
image: nodered/node-red:latest
environment:
- TZ=Europe/Amsterdam
ports:
- "2000:1880"
networks:
- node-red-net
volumes:
- node-red-data:/home/user/node-red1
volumes:
node-red-data:
networks:
node-red-net:
However, even though this file works fine when I run docker-compose up, the volume exists only inside the docker machine. I've tried adding the line external: true in volumes but I get the following error:
ERROR: In file './docker-compose.yml', volume 'external' must be a mapping not a boolean.
What am I missing? How do I mount an external volume using docker-compose files?

Answer 1

I ended up finding a related question with this answer. There are multiple answers that didn't work for me there (also there's no accepted answer). The syntax that worked was:
node-red-data:
driver: local
driver_opts:
o: bind
type: none
device: /path/external/folder
So the final dockerfile that works after running docker-compose up is:
version: "3.7"
services:
node-red:
image: nodered/node-red:latest
environment:
- TZ=Europe/Amsterdam
ports:
- "2000:1880"
networks:
- node-red-net
volumes:
- node-red-data:/data
container_name: node-red
volumes:
node-red-data:
driver: local
driver_opts:
o: bind
type: none
device: "/home/user/node-red1"
networks:
node-red-net:
Update
If we don't mind having a random name for the volume, the following solution also works fine:
version: "3.7"
services:
node-red:
image: nodered/node-red:latest
environment:
- TZ=Europe/Amsterdam
ports:
- "2000:1880"
volumes:
- /home/user/node-red1:/data
container_name: node-red