Docker Named Volume with targeting windows local folder - docker-compose

Question

In docker-compose file I want to create a named volume which will target local drive for test purposes. For production we will use NFS.
I created the compose file as following,
version: '3.3'
services:
test:
build: .
volumes:
- type: volume
source: data_volume
target: /data
networks:
- network
volumes:
data_volume:
driver: local
driver_opts:
o: bind
type: none
device: c:/data
networks:
network:
driver: overlay
attachable: true
When I run the docker-compose up, I got the following error,
for test_test_1 Cannot create container for service test: failed to mount local volume:
mount c:/data:/var/lib/docker/volumes/test_data_volume/_data, flags: 0x1000: no such file
or directory
Even with errors, it still creates the named volume. So when I inspect it,
{
"CreatedAt": "2019-10-07T09:10:14Z",
"Driver": "local",
"Labels": {
"com.docker.compose.project": "test",
"com.docker.compose.version": "1.24.1",
"com.docker.compose.volume": "data_volume"
},
"Mountpoint": "/var/lib/docker/volumes/test_data_volume/_data",
"Name": "test_data_volume",
"Options": {
"device": "c:/data",
"o": "bind",
"type": "none"
},
"Scope": "local"
}
I'm still not sure why the Mountpoint is targeting that location.
I know I can achieve this without named volume (which I already did), but for future in the project we definitely need named volume.
Any suggestion how to achieve this?

Answer 1

Same here. Using Docker Desktop for Windows, I tried to mount the local path E:\Project\MyWebsite\code to the named volume but failed. Here's how I sorted this out.
First, I changed the path to ".":
volumes:
website:
driver: local
driver_opts:
type: none
device: "."
o: bind
This time docker-compose up ran successfully, so I logged into the shell and checked how the mounted directory looks like:
bash-5.0# ls -l
total 62
lrwxrwxrwx 1 root root 11 Oct 1 15:15 E -> /host_mnt/e
drwxr-xr-x 2 root root 14336 Sep 11 15:27 bin
drwxr-xr-x 4 root root 2048 Apr 19 2017 dev
lrwxrwxrwx 1 root root 11 Oct 1 15:15 e -> /host_mnt/e
drwxr-xr-x 1 root root 180 Sep 30 11:53 etc
drwxr-xr-x 2 root root 2048 Sep 11 15:27 home
drw-r--r-- 4 root root 80 Oct 8 22:52 host_mnt
drwxr-xr-x 1 root root 60 Sep 30 11:53 lib
drwxr-xr-x 5 root root 2048 Sep 11 15:27 media
...
drwxrwxrwt 1 root root 40 Oct 11 19:37 tmp
drwxr-xr-x 1 root root 80 Sep 11 15:27 usr
drwxr-xr-x 13 root root 2048 Sep 11 15:27 var
Obviously not a Windows volume, probably some Linux VM created by Docker. But the paths /host_mnt/e and /host_mnt/E seem indicative, so I tried changing the docker-compose definition to:
volumes:
website:
driver: local
driver_opts:
type: none
device: "/host_mnt/e/Project/MyWebsite/code"
o: bind
And it worked! Looks like named volume doesn't work the same as the ordinal way for Windows.
This /host_mnt/e probably won't exist unless the you've granted access to the drive letter before. But this shouldn't be an issue to you, as you'd tried the ordinal way of mounting a local drive which worked.