Steps:

 1. Create and Attach an IAM role with "CloudWatchFullAccess" policy to the EC2 instance as follows

• Open the IAM console --> Create Role --> apply.
• Attach the created Role to the EC2 instance.

2. To install and configure CloudWatch Logs on an existing Ubuntu Server instance

• Connect to the EC2 instance,
• On EC2 instance, run the following commands before installing CloudWatch Log

         sudo apt update
         sudo apt install python3

• To install and configure CloudWatch Logs directly from the internet

         curl https://s3.amazonaws.com/aws-cloudwatch/downloads/latest/awslogs-agent-setup.py -O

• Run the following command to setup system and custom application logs

        sudo python ./awslogs-agent-setup.py --region us-east-1

• awslogs.conf file content located at /var/awslogs/etc/

• Use the following command to view the awslogs.log file

        sudo tail -f /var/log/awslogs.log

• Navigate to Cloudwatch --> Log Groups to view the applogs and syslog log entries create by Cloudwatch agent.

• Use the following commands to start,stop and get the status of agent service.

        sudo service awslogs start
        sudo service awslogs stop
        sudo service awslogs status

Information:

CloudWatch retains metric data as follows:

1. Data points with a period of less than 60 seconds are available for 3 hours. These data points are high-resolution custom metrics.
2. Data points with a period of 60 seconds (1 minute) are available for 15 days
3. Data points with a period of 300 seconds (5 minute) are available for 63 days
4. Data points with a period of 3600 seconds (1 hour) are available for 455 days (15 months)

CloudWatch does not support metric deletion. Metrics expire based on the retention schedules described above.

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