Day 19 Task: Docker for DevOps Engineers

Docker Volume:

Docker volume is a persistent data storage mechanism in Docker containers that allows data to persist even after the container is destroyed or recreated. It provides a way to share data between containers and between a container and the host system.

A volume is a directory within the Docker host's file system that is accessible by one or more containers. When a container is created, a volume can be attached to it by specifying the volume name or the path to the volume in the container's configuration. Any data written to the volume from within the container will be stored in the volume on the host's file system.

Ejemplos de Docker

Update CLI
```
  apt-get update
```

Install Docker
```
  apt-get install docker.io -y
```

Check Docker Status
```
  service docker status
```

Here I am creating a docker file in which I will install nginx and create a volume inside a container with path /etc/Aman.

# Use the official nginx image as the base image
FROM nginx

# Create a volume inside the container at /etc/Aman
VOLUME /etc/Aman

# Expose port 80 for nginx
EXPOSE 80

# Start nginx when the container starts
CMD ["nginx", "-g", "daemon off;"]

Now create image from Docker file

docker build -t <image_name>

Now Check Image Create or Not

docker images

Now create a 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 files on 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++++++++++++++++++++++++

Day 19 Task: Docker for DevOps Engineers

Table of contents

Docker Volume:

Sharing Data Between Containers:

Volume by command and shared between Two Container

Shared volume by host to container