If I would like to create a data volume of let´s say 15GB that would be of type ext4, how would I do that?
docker volume create --name vol
just creates an empty volume.
docker volume create --opt type=ext4 --name vol
creates an ext4 volume but I cannot specify the size of it since ext4 does not support it according to the mount options of ext4.
It is possible to specify the size limit while creating the docker volume using size
as per the documentation
Here is example command provided in the documentation to specify the same
docker volume create -d flocker -o size=20GB my-named-volume
UPDATE Some more examples from git repository:
The built-in local driver on Linux accepts options similar to the linux mount command:
$ docker volume create --driver local --opt type=tmpfs --opt device=tmpfs --opt o=size=100m,uid=1000
Another example:
$ docker volume create --driver local --opt type=btrfs --opt device=/dev/sda2