> For the complete documentation index, see [llms.txt](https://mamawhocode.gitbook.io/aws/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mamawhocode.gitbook.io/aws/services/monitoring/cloudwatch.md).

# CloudWatch

native monitoring service

## Overview

* Sevice used for monitoring the ***cloud*** and ***on-premises*** systems (using CloudWatch agent).

### State of Alarm

* `INSUFFICIENT_DATA`: alarm has just started, the metric is not available, not enough data.
* `OK`: within the threshold
* `ALARM`: outside of the defined threshold.

### Benefits

* Single platform observability (both AWS resources and on-premises servers).
* Easy metrics collection. Natively integrate with 70+ AWS services.
* Improve performance and resource optimization

***

## Features

### Default EC2 metrics

By default, CloudWatch provides these metrics:

* CPU utilization
* Network utilization
* Disk I/O

It *<mark style="color:red;">does not natively provide memory and disk space utilization metrics</mark>*.  You need to install [CloudWatch agent](/aws/services/monitoring/cloudwatch.md#cloudwatch-agent) to collect these metrics. Some other metric that unavailable:

* Memory utilization
* Disk swap, disk space utilization
* Page file utilization
* Log collection

### CloudWatch Agent&#x20;

* Used to collect data from on-prem systems.
* Support both Windows, Linux
* **Configuration file**: a JSON file that specifies the metrics and logs that the agent is to collect.

### Metrics `Lambda` send to CloudWatch

* Invocation
* Duration
* Errors
* Throttles
* DeadLetterErrors
* IteratorAge
* ConcurrentExecutions
* UnreservedConcurrentExecutions&#x20;

***

## Concepts

* ***Metric***: a time-ordered set of data points that are published to CloudWatch.
* ***Namespace***: a container for CloudWatch metrics.
* ***Dashboard***: are customizable home pages in the CloudWatch console.

## Trivia

* Data is available in 5-minute periods. If you enable `Detailed monitoring`, data will be available in 1-minute periods.
* Dashboard are global. That means you can access dashboard from anywhere.
* If you want people to access Dashboard only, try to use [CloudWatch Dashboard sharing](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch-dashboard-sharing.html).

### KMS

* CloudWatch Logs supports only *<mark style="color:red;">**symmetric**</mark>* customer managed keys. Do not use an asymmetric key to encrypt the data in your log groups.
* To encrypt a log group with a customer managed key, you need to use the AWS CLI or SDKs. The steps would be:

1. Create a customer managed ***symmetric*** KMS key
2. Add policy to KMS key for CloudWatch to use the created key `"Service": "logs.region.amazonaws.com"`
3. Associate the KMS key with the log group

```bash
aws logs associate-kms-key --log-group-name logGroupName --kms-key-id keyArn
```

4. Any new log events ingested into the log group ***after*** associating the KMS key will be encrypted using that key


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://mamawhocode.gitbook.io/aws/services/monitoring/cloudwatch.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.