CloudWatch

Overview

• CloudWatch provides metrics for every service in AWS

• Metric is a variable to monitor (CPUUtilization, NetworkIn...)

• Metrics have timestamps

• Can create CloudWatch dashboards of metrics

Example: CloudWatch Billing metric

Important Metrics

• EC2 instances: CPU Utilization, Status Checks, Network (not RAM)

• Default metrics every 5 minutes

• Option for Detailed Monitoring ($$$): metrics every 1 minute

• EBS volumes: Disk Read/Writes

• S3 buckets: BucketSizeBytes, NumberOfObjects, AllRequests

• Billing: Total Estimated Charge (only in us-east-1)

• Service Limits: how much you’ve been using a service API

• Custom metrics: push your metrics

CloudWatch Alarms

• Alarms are used to trigger notifications for any metric

• Alarms actions...

• Auto Scaling: increase or decrease EC2 instances “desired” count

• EC2 Actions: stop, terminate, reboot, or recover an EC2 instance

• SNS notifications: send a notification to an SNS topic

• Various options (sampling, %, max, min, etc...)

• Can choose the period on which to evaluate an alarm

• Example: create a billing alarm on the CloudWatch Billing metric

• Alarm States: OK. INSUFFICIENT_DATA, ALARM

CloudWatch Logs

• CloudWatch Logs can collect log from:

• Elastic Beanstalk: collection of logs from application

• ECS: collection from containers

• AWS Lambda: collection from function logs

• CloudTrail based on filter

• CloudWatch log agents: on EC2 machines or on-premises servers

• Route53: Log DNS queries

• Enables real-time monitoring of logs

• Adjustable CloudWatch Logs retention

CloudWatch Logs for EC2

• By default, no logs from your EC2 instance will go to CloudWatch

• You need to run a CloudWatch agent on EC2 to push the log files you want

• Make sure IAM permissions are correct

• The CloudWatch log agent can be setup on-premises too