🌟Docker Swarm on AWS Cloud🌟
Swarm is Docker tool used to create Cluster,Docker Swarm mode is built into the Docker Engine.
Docker swarm have two types of nodes :
1.Master node / Controller npde
2.Worker node / Slaves node
☀️Creating four nodes Swarm cluster☀️
In this practical Creating Docker cluster , we take four AWS insatnce one of that instane make Master node & remaining nodes make worker node.
Prerequisite:
1.AWS account & Ec2 instance knowledge
2.In all four instances install docker and start service
#yum install docker -y
#systemctl start docker
#docker info
🏷️Step 1- Make one node master node ,the node which want to make master that node Ip address is required in my case i want make master node IP of that instance 172.31.37.180 . Note:To check IP use "ifconfig" command , use eth0 IP to make Swarm cluster
Docker swarm init command is used to make cluster
#docker swarm init --advertise-addr 172.31.37.180
🔔Here get one Token that paste in remaining instance that want to be make worker node
🏷️Step 2-
Paste token in three instance (docker must be installed & service start)
🏷️Step 3-
Here Docker Swarm cluster is created to check use "docker info", om master node
#docker node ls
⭐Why use Docker swarm ❓
Swarm master node keep watching on Container or Task ,if any Container goes down for any reason or Fault occurs , Master node auto-matically create same task on any Node.This is known a"fault tolerance".
💫Load balancer & Scaling on Docker Swarm 💫
⚡Replication:
Swarm cluster give capability to make exact copy of task in another node this concept is called as Replication.
💥Load Balancer:
Docker swarm give pre-created set-up of load balancer, In docker Swarm 'Load balancer'term is "Service". "Load Balancer=Service"
Docker service (Load Balancer) is by default isolated ,It can't connect outside world it only connect to Cluster nodes, But if we want to make connection to outside world , we use"--publish",patting,expose.
🌟Scaling :
There are two types of Scaling Vertical scaling and Horizontal scaling,We use Horizontal scaling.
Adding more containers or instance are called as 'Scale-out'& removing Containers or instances is called 'scale-in'.
🔔To start any service in cluster we use 'Master node',The master node tracks the status of tasks & monitors the health of the cluster.
🏷️Steps -
On Master node:(To start service'Load balancer)
#docker service create --name myweb55 --publish 8080:80 vimal13/apache-webserver-php
#docker service ls <<--- Check service ls
#docker service ps myweb55 <<-- this show where Task lauch
For scale-out
#docker service scale myweb55=5
For scale-in
#docker service scale myweb55=1
❄️check on Google/Browser
Public IP of master instance + port no.(http://13.201.15.80:8080/)
