Docker is an open platform that allows developers and sysadmins to build and run distributed applications using lightweight Linux containers. It provides portable deployments, fast application delivery, and allows applications to be easily scaled and deployed. Docker uses a client-server architecture with Docker daemons managing container operations. Images are packaged applications that serve as the basis for containers, which provide isolated execution environments for running applications.

1. LINUX CONTAINERS AND
DOCKER OPEN PLATFORM
Rahul More

3. Docker is an open platform for developers and
sysadmins to build, ship, and run distributed
applications

4. ?
• “an open source platform to pack, ship and
run any application as a lightweight linux
container.”
• “chroot on steroids.”

6. TRADITIONS
VM vs Docker

7. WHY TO USE DOCKER-
MINGLE
• Developers
• QA
• Nebulous SYS Admins-
ish

8. DEVELOPER
S
“works on my machine”

9. QA
“does not work on my test
environment”

10. SYS ADMIN
“I want my weekend”

11. WHY USE DOCKER?
• Portable deployments.
• Fast Application delivery.
• Scale and deployed with ease.
• Higher workloads - greater density.

12. Dev App Container
Tester
Container
Sys Admin Automation
ProductionEnvironments

13. TRADITIONS
VM vs Docker

14. DOCKER
ARCHITECTURE

15. DOCKER
• Client Server Architecture.
• Socket or REST APIs
• Docker Daemon
• All container operations
• Docker Client
• Main interface between user
and docker daemon.
• Docker Internal Components.

16. DOCKER COMPONENTS
• Docker Internal Components
• Docker Image
• Similar to OS disk images.
• Used as base , layers build upon the base image[Layer
0].
• Portable.
• Docker Registry
• Repository of Docker Images.
• Public or Private.
• Docker Containers
• Running Images
• Directory + Execution Environment.
• Isolated.
• User Space + Networking + Security Components.
Docker
Image
Kernal
Docker
Engine
Docker
Registr
y
Docker
Container

17. WORKING OF DOCKER
• Docker Image.
• Each image is
association of images.
• Layered approach for
abstraction.
• Unified file system.
Each layer as a
directory.
• Dockerfile.
Base Image
Layered Image-2[add
apache]
Running Container [php
application
Layered Image-2[add php]
Layered Image-3[add mysql]
Reference Image

18. WORKING OF DOCKER
• Docker Registry.
• All images are stored
in a client.
• Private or public.
• Images are pulled and
pushed in a registry.

19. WORKING OF DOCKER
• Docker Container.
• Run time environment.
• Command from REST
API/Docker Binary to
run the container.
• sudo docker run -i -t
ubuntu /bin/ bash
Docker client
Docker Daemon
Container
Pulled Image
REPOSITORY
Creates Containers from Image
Binary API Request

20. DOCKER
• sudo docker run -i -t ubuntu /bin/ bash
• Docker client will be launched with
“docker run” command.
• It tells the daemon, from which
image the container should be
created. In our example, it is a
Ubuntu image.
• “-i” tells the Docker daemon to run
the container in interactive mode.
• “-t” represents tty mode for
interactive session.
• “/ bin/ bash” tells the Docker
daemon to start the bash shell when
the container is launched.
Docker client
Docker Daemon
Container
Pulled Image
REPOSITORY
Creates Containers from Image
Binary API Request

21. DOCKER
• Successful Execution of run.
• Checks for the image.
• Pulls the image to create a container.
• Creates a read/write filesystem over
the image.
• Creates a network interface for the
container to interact with host
machine.
• Checks for IP . Allocates IP.
• Executes the command specified.
• Logs.
Docker client
Docker Daemon
Container
Pulled Image
REPOSITORY
Creates Containers from Image
Binary API Request

22. IMMUTABLE
INFRASTRUCURE
• Immutable infrastructure comprises of
immutable components and for every
deployment the components will be replaced
with the updated component rather than
being updated.

23. DEMO
• A static web application
running on apache.
• A mysql Image.
• Wordpress application with
MYSQL db.
• Hosting multiple websites
on docker host.
• Building and testing
containers using Jenkins CI.