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Cloud Watch
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=> It is used for monitoring aws resources.

=> CloudWatch enables real-time monitoring of AWS resources such as Ec2 , EBS volumes, Elastic Load Balancing and RDS instances. 

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Usecase
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=> Create EC2 instance in aws cloud

=> Monitor that EC2 Instance 24/7

=> If Ec2 instance CPU utilization is above 90 % then trigger alarm.

=> When alarm got triggered send email notification to management.

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How to send Email notification in AWS
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=> In AWS we have SNS to send notifications

	SNS : Simple Notifcation Service

=> SNS works based on Pub and Sub Model

	Pub => Publisher (will send msg to sns topic)

	Sub => Subscriber (will recieve msg from topic)

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Cloud Watch & SNS - Lab Task
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1) Create SNS Topic with Email Notification (Standard Create)

		Topic Name : ashokit

2) Configure Email Subscription in SNS Topic (Confirm Subscription recieved in email)

3) Create EC2 Instance and Configure Cloud Watch Alaram To Monitor 

-> Select EC2 Instance -> Action -> Monitor and trouble Shoot -> Manager Cloud Watch Alarms -> Create cloud watch  Alarm
    
  Alaram Notification : Select SNS Topic which we have created
  Alaram Thresh Hold : Avg CPU Utiliation >= 5%

4) Connect to EC2 VM using ssh client and increase load 

  $ sudo yum install stress -y
  $ sudo stress --cpu 8 -v --timeout 180s

Note: Execute stress command 3 to 4 times...

5) Observe the behaviour of Cloud Watch / Alaram / SNS  
    (We should get Email Notification)

Note: When Alarm got triggered, its status will be changed to 'In Alarm'

=> We can Monitor our Alarm history (how many times it got triggered)
	
	(Goto Cloud Watch -> Select Alarms -> Click Alarm -> Click on History).