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Docker Volumes Deep Dive

By design, Docker containers do not store persistent data. Any data written to a container’s writable layer will no longer be available once the container stops running. Also, getting data written to a container back out of it for another process can be difficult. To solve the issue of persisting data from a container docker uses volumes

• docker volume ls command will show all volumes
• Lets create one

• Lets Create another one and inspect

• You can see those volumes mounted on /var/lib/docker/volumes/

• Lets attach this volume to a new container. (-v vikivol:/vol and --mount source=<vol_name>,target=<cont_mnt_dir> are same however mount is preferred)

• Now lets look into the volume. the Host machines directory is actually mounted into the container

• This volume is persitent. even if you delete the container the volume with data will persist
• If you try to delete a volume which is being used by a container it will not be deleted thats a safety latch.