How to create docker volume device/host path
create a volume.
$ docker volume ls | grep my-volume
$ docker run -it --rm -d --name tmp -v my-volume:/mnt alpine
$ docker volume ls | grep my-volume
local my-volume
$ docker exec tmp ls -l /mnt
total 0
$
Copy a file to a container.
$ docker cp . tmp:/mnt
$ docker exec tmp ls -l /mnt
total 4
-rw-r--r-- 1 501 50 93 Apr 20 22:53 Dockerfile
$ ls
Dockerfile
$
clean up.
$ docker rm -f tmp
tmp
$
check.
$ docker run --rm -v my-volume:/mnt alpine ls /mnt
Dockerfile
$
Approach #1 - COPY
To copy the file from the host to the container
docker cp /path/of/the/file <Container_ID>:/path/of/he/container/folder
Issue with the above approch is, it will not persists the volume or file or dir, as you remove the container it will be lost. This is suggested only for temporary pupose.
Approach #2 - Volume Mounting
Mouting the volume from the host to container
Step1: Create the volume with the custom path
docker volume create --name my_test_volume --opt type=none --opt device=/home/jinna/Jinna_Balu/Test_volume --opt o=bind
Step2 : Mount to the container or swarm service
docker run -d \
--name devtest \
--mount source=my_test_volume,target=/app \
nginx:1.11.8-alpine
We can do both of the above steps with below .yaml files
version: '3'
services:
nginx:
image: nginx:1.11.8-alpine
ports:
- "8081:80"
volumes:
- my_test_volume:/usr/share/app
volumes:
my_test_volume:
driver: local
driver_opts:
o: bind
type: none
device: /home/jinna/Jinna_Balu/Test_volume
RUN the above yml with docker-compose
docker-compose up -d
NOTE: create the folder path before you do docker-compose.
Good practice to have files mouted to maintain the persistency.