AWS CloudWatch Metrics

• CloudWatch provides metrics for every services in AWS
• Metric is a variable to monitor (CPUUtilization, NetworkIn…)
• Metrics belong to namespaces
• Dimension is an attribute of a metric (instance id, environment, etc…)
• Use API call PutMetricData to send custom metrics into CloudWatch

CloudWatch Logs

• Log groups: arbitrary name, usually representing an application
• Log stream: instances within application / log files / containers
• Can define log expiration policies (never expire, 30 days, etc..)
• CloudWatch Logs can send logs to:
  • Amazon S3 (exports)
  • Kinesis Data Streams
  • Kinesis Data Firehose
  • AWS Lambda
  • OpenSearch
• CloudWatch Logs can use filter expressions
  • For example, find a specific IP inside of a log
  • Or count occurrences of “ERROR” in your logs
• Metric filters can be used to trigger CloudWatch alarms
• CloudWatch Logs Insights can be used to query logs and add queries to CloudWatch Dashboards

CloudWatch Alarms – Composite Alarms

• CloudWatch Alarms are on a single metric

• Composite Alarms are monitoring the states of multiple other alarms

• AND and OR conditions

  

• Alarms can be created based on CloudWatch Logs Metrics Filters

CloudWatch Synthetics Canary