day4.txt

What is a Docker Swarm?
=========================

A Docker Swarm is a group of either physical or virtual machines that are running the Docker application and that have been configured to join together in a cluster. Once a group of machines have been clustered together, you can still run the Docker commands that you're used to, but they will now be carried out by the machines in your cluster. The activities of the cluster are controlled by a swarm manager, and machines that have joined the cluster are referred to as nodes.

Docker swarm is a container orchestration tool, meaning that it allows the user to manage multiple containers deployed across multiple host machines..

One of the key benefits associated with the operation of a docker swarm is the high level of availability offered for applications. In a docker swarm, there are typically several worker nodes and at least one manager node that is responsible for handling the worker nodes' resources efficiently and ensuring that the cluster operates efficiently.




To create Docker Swarm
========================
docker swarm init --advertise-addr=192.168.0.8 

Swarm initialized: current node (ki99an0dnuhzeosjz0nve6wl1) is now a manager.

To add a worker to this swarm, run the following command:

    docker swarm join --token SWMTKN-1-03r7a85clnd551byp3hnpks4g0qp834kl0lrzztzctdojqeo2x8jrhhi3ghfvj2prnn4pihxp5q 192.168.0.8:2377

To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.



Usage:  docker node COMMAND

Manage Swarm nodes

Commands:
  demote      Demote one or more nodes from manager in the swarm
  inspect     Display detailed information on one or more nodes
  ls          List nodes in the swarm
  promote     Promote one or more nodes to manager in the swarm
  ps          List tasks running on one or more nodes, defaults to current node
  rm          Remove one or more nodes from the swarm
  update      Update a node



Usage:  docker service COMMAND

Manage services

Commands:
  create      Create a new service
  inspect     Display detailed information on one or more services
  logs        Fetch the logs of a service or task
  ls          List services
  ps          List the tasks of one or more services
  rm          Remove one or more services
  rollback    Revert changes to a service's configuration
  scale       Scale one or multiple replicated services
  update      Update a service


To create 3 nginx containers
===============================
docker run --name a-nginx -p 1111:80 -d nginx
docker run --name b-nginx -p 2222:80 -d nginx
docker run --name c-nginx -p 3333:80 -d nginx

create p-nginx-service
=======================
docker service create --name p-nginx --replicas 3 --publish 1111:80 nginx

docker service create --name p-cafe --replicas 10 --publish 4444:80 pradeepch82/pradeep-cafe:1.1

docker service create --name p-tea --replicas 10 --publish 3333:80 pradeepch82/tea:1.1


docker service update --replicas 10 p-tea

docker service update --replicas 5 p-tea

docker service update --image pradeepch82/tea:1.2 p-tea
docker service update --image pradeepch82/tea:1.3 p-tea
docker service update --image pradeepch82/tea:1.4 p-tea

docker service update --replicas=5 --image pradeepch82/tea:1.4 p-tea

docker service scale p-tea=12 p-coffee=5 p-lunch=6

docker service update --image pradeepch82/tea:1.3 --publish-add published=5555,target=80 p-tea

docker service update --image pradeepch82/tea:1.3 --publish-add published=1111,target=80 p-tea

docker service update --image pradeepch82/tea:1.3 --publish-rm p-tea

Day3
====
Docker Stack
=================
Usage:  docker stack [OPTIONS] COMMAND

Manage Docker stacks

Options:
      --kubeconfig string     
                Kubernetes config file
      --orchestrator string   
                Orchestrator to use
                (swarm|kubernetes|all)

Commands:
  deploy      Deploy a new stack or update an existing stack
  ls          List stacks
  ps          List the tasks in the stack
  rm          Remove one or more stacks
  services    List the services in the stack



Creating the wp-mysql-stack
============================


docker-compose.yml
=====================
version: '3.3'
services:
   db:
     image: mysql:5.7
     volumes:
       - db_data:/var/lib/mysql
     restart: always
     environment:
       MYSQL_ROOT_PASSWORD: somewordpress
       MYSQL_DATABASE: wordpress
       MYSQL_USER: wordpress
       MYSQL_PASSWORD: wordpress

   wordpress:
     depends_on:
       - db
     image: wordpress:latest
     ports:
       - "8000:80"
     restart: always
     environment:
       WORDPRESS_DB_HOST: db:3306
       WORDPRESS_DB_USER: wordpress
       WORDPRESS_DB_PASSWORD: wordpress
       WORDPRESS_DB_NAME: wordpress
volumes:
    db_data: {}

==========================================================================

docker stack deploy --compose-file docker-compose.yml wp-mysql-stack
docker stack ls
docker stack ps wp-mysql-stack
docker stack services wp-mysql-stack
docker stack rm wp-mysql-stack






docker-compose.yml
===================
version: '3.3'

services:
   database:
     image: pradeepch82/ems-mysql:1.1
     volumes:
       - db_data:/var/lib/mysql
     restart: always
   ems-spring-boot:
     depends_on:
       - database
     image: pradeepch82/pvc-spring-boot-ems:1.2
     ports:
       - "1212:8080"
     restart: always
     
volumes:
    db_data: {}


docker stack deploy --compose-file docker-compose.yml pvc-springboot-mysql



docker-compose.yml
===================
version: '3.3'

services:
   database:
     image: pradeepch82/ems-mysql:1.1
     deploy:
      replicas: 3
     volumes:
       - db_data:/var/lib/mysql
     restart: always
     networks:
       - backendNetwork
       - frontendNetwork
   ems-spring-boot:
     depends_on:
       - database
     image: pradeepch82/pvc-spring-boot-ems:1.2
     deploy:
      replicas: 1
     ports:
       - "1212:8080"
     restart: always
     networks:
       - frontendNetwork
  
volumes:
    db_data: {}
networks:
  backendNetwork:
  frontendNetwork:



docker stack deploy --compose-file docker-compose.yml pvc-springboot-mysql


============================================
docker-compse with swarm
============================
version: '3'

services:
  database:
    image: pradeepch82/ems-mysql:1.1
    deploy:
      replicas: 2
    container_name: database
    volumes:
     - dockerAngularSpringDatabaseData:/var/lib/mysql
    networks:
     - backendNetwork
     
  spring-boot-ems:
    image: pradeepch82/pvc-spring-boot-ems:1.2
    deploy:
      replicas: 3
    ports:
      - 1212:8080
    depends_on:
      - database
    networks:
      - backendNetwork
      - frontendNetwork
     
  ems-angular-app:
    image: pradeepch82/ems-angular-app:1.2
    deploy:
      replicas: 3
    ports: 
      - 4200:80
    depends_on:
      - spring-boot-ems
    networks:
      - frontendNetwork

volumes:
  dockerAngularSpringDatabaseData:
  
networks:
  backendNetwork:
  frontendNetwork:



docker stack deploy --compose-file docker-compose.yml angular-spring-mysql-stack





Day4
=====================================================================
To start a single container from image                   : docker run

To start a multiple container in one command             : docker-compose up -d 

To start a multiple containers via service in swarm      : docker service create

To start a multiple services in swarm                    : docker stack deploy

docker service update --replicas 5 pvc-springboot-mysql_database

docker service scale  pvc-springboot-mysql_ems-spring-boot=3 pvc-springboot-mysql_database=7

docker events --filter 'event=stop'
docker events --filter 'event=start'
docker events --filter 'event=create'



docker volume    : used to share the data among containers
==============
docker volume ls
docker volume create p-mysql-volume



docker run --name a-mysql -v p-mysql-volume:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=admin -e MYSQL_DATABASE=company  -d mysql:5.7


docker exec -it a-mysql bash
mysql -uroot -padmin
use company

create table employee(id int primary key,name text);
insert into employee values(101,'Pradeep');
insert into employee values(102,'Sachin');
insert into employee values(103,'Sunil');
select * from employee;

exit  
exit

docker stop a-mysql
docker rm a-mysql;


docker run --name b-mysql -v p-mysql-volume:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=admin -e MYSQL_DATABASE=company  -d mysql:5.7


docker exec -it b-mysql bash
mysql -uroot -padmin
use company
select * from employee; 






















docker history pradeepch82/ems-mysql:1.1





docker volume create pvc-vol
	
docker service create --name p-nginx --mount type=volume,source=pvc-vol,target=/usr/share/nginx/html --replicas 3 -p 2222:80 nginx



Docker Swarm Volumes.
=========================
Swarm might not look as mature as Kubernetes: 
It only comes with one type of volume natively, which is a volume shared between the container and its Docker host. This might come in handy for testing a deployment locally, but it won't do the job on a distributed cluster.