Volume

Volumes are the preferred mechanism for persisting data generated by and used by Docker containers. While bind mounts are dependent on the directory structure and OS of the host machine, volumes are completely managed by Docker. Volumes have several advantages over bind mounts:

• Volumes are easier to back up or migrate than bind mounts.

• You can manage volumes using Docker CLI commands or the Docker API.

• Volumes work on both Linux and Windows containers.

• Volumes can be more safely shared among multiple containers.

• Volume drivers let you store volumes on remote hosts or cloud providers, to encrypt the contents of volumes, or to add other functionality.

• New volumes can have their content pre-populated by a container.

• Volumes on Docker Desktop have much higher performance than bind mounts from Mac and Windows hosts.

  Docker has two options for containers to store files in the host machine so that the files are persisted even after the container stops:

  1. Volumes are stored in a part of the host filesystem, which is managed by

  2. Bind mountsmay be stored anywhere on the host system.

• Step for Install Docker in Ubuntu

  1. update the local system

•   apt-get update
  

  

  2. Now Install Docker

    apt-get install docker.io -y
  

  

  3. Now Check Docker Status

•   service docker status
  

  

  • To Delete Container

    docker rm <container_name>

• To Create a Conatiner

    docker volume create <volume_name>

• To Check Volumes

    docker voolume ls

Steps For Creating Volume

• Volume by Docker File

• Volume by command and shared between two container

• Shared volume by host to container

1. Volume by Docker File

   creating file Docker name ex vi Dokcerfile

   

Now create image from Docker file

docker build -t <image_name>

Now Check Image create or Not

docker images

Now create Container from that Images

Docker run -it --name <container_name> <image_name> /bin/bash

now check container

docker ps -a

Now start the container

docker start <container_id>

Now go inside the container

docker attach <container_id>

now create some file in myvolume and exit from conatiner

touch filex filey filez

Now create new continer from update container

docker run -it --name cont_2 --privileged=true --volumes-from cont_1 ubuntu /bin/bash

so here container is created and volume ""myvolume"" is attach is both container all th3 files are there.

• Volume by command and shared between Two Container

  •   docker run -it --name <continer_name> -v /<vomlumename> <image_name> /bin/bash
    

now create another container from update container

•   docker run -it --name <container_name> --privileged=true --volumes-from <container_name> <image_name> /bin/bash
  

• 

  Now We added some file is this container and check on con_4 file automated added or no in volumes

• 

• Now Created some file in con_3 and exit from cont_3

  

  Now Start and Attach the Container_4 and see that changes

    docker start <container_id>
    docker attach <container_id>
  

• 

  Now see the Change here volume is shared in each container once we update in any file its automatically updated in both volumes of both container

• 

Shared volume by host to container

create a 3 fileson your local system

touch devops aws linux

Now Create Conatiner at local Ubuntu

docker run -it --name <container_name> -v /home/ubuntu:/<volume_name> --privileged=true <image_name> /bin/bash

Now Volume is Created and all the file are in Local Ubuntu are shared with Hostvolume

Now Update on Host-Volume and see the change is Aman

ThanK You