What is difference between CloudWatch Agent and default EC2 monitoring?

Question

By default, EC2 monitoring already sends metrics such as CPU utilization to CloudWatch.

1) So does that mean a CloudWatch agent already installed into an EC2 by default?

2) If no, then how EC2 sends CPU metrics to CloudWatch?

3) Install a CloudWatch Agent is to send log files to CloudWatch Logs?

Thank you,

Accepted Answer

1. No, there is no mentioned of EC2 having a CloudWatch agent installed in it by default in the documentation.
2/3. The EC2 service push the basic metrics such as CPU/Network Utilization and Disk Performance to CloudWatch. Having CW Agent installed in your EC2 offers access to the system level metrics:

Metrics collected by the CloudWatch agent - Metrics collected by the CloudWatch agent on Linux and macOS instances - https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/metrics-collected-by-CloudWatch-agent.html#linux-metrics-enabled-by-CloudWatch-agent

This also supports being able to collect the system level logs from your EC2 and be stored in CW Logs.

What is difference between CloudWatch Agent and default EC2 monitoring?

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