Cloudwatch Terms

• Metric: Any measurable unit of the Infrastructure/Application/Platform. Eg CPU Utilization, Disk Read Bytes, Network Packets Out

• Unit: measurement unit generally something like Bytes/Sec, Percentages

• TimePeriod: Duration of the metric

• Aggregations: Min, Max, Sum, Count, Average, Percentile

• Alarm: Is state when something measurable is wrong.

  • When CPU Utilzation is > 85% for 10 mins
  • When free disk space < 1GB
  • When Network Packets IN == 0 for 10 mins

• Alarm States:

  • Alarm: When the Alarm condition is met for eg CPU Utilization is > 85% for over 10 mins
  • OK: When Alarm condition is not met for eg CPU Utilization is == 74% for over 10 mins
  • Insufficient: Cloudwatch doesnot have data of timeperiod. eg Instance has been create 2 mins ago. Data is not sufficent to recognize the alarm or ok state.

Basic Cloudwatch Alarming

• Workflow

• Alarms can do the following action when state is ALarm

  • Send Notifications using SNS
  • EC2 AutoScaling Action
  • EC2 Actions

AWS CloudWatch Overview

note: From official AWS docs

Next Steps

• Cloudwatch and EC2
• Cloudwatch and RDS
• Cloudwatch and ELB
• Other Service Integrations