This is a very simple exploration of AWS CloudWatch from the AWS CLI. To get started with the CLI first install it, then use aws configure to configure it for your account and region.
There are numerous areas to explore with CloudWatch and I’m doing my work in us-west-2.
Alarms
Did it work? What is out there?
aws cloudwatch describe-alarms
Create Alarm
aws cloudwatch put-metric-alarm --alarm-name MyCPUAlarm --alarm-description "Alarm when CPU exceeds 70 percent" --metric-name CPUUtilization --namespace AWS/EC2 --statistic Average --period 300 --threshold 70 --comparison-operator GreaterThanThreshold --dimensions "Name=InstanceId,Value=i-00b9f133ae1a5e033" --evaluation-periods 2 --alarm-actions arn:aws:sns:us-west-2:100935286947:MySNSTopic --unit Percent
Test Fire an Alarm
aws cloudwatch
Disable/Enable Alarm
Note: Alarm state will still change but alarms won’t fire
aws cloudwatch disable-alarm-actions --alarm-names MyCPUAlarm
aws cloudwatch enable-alarm-action --alarm-names MyCPUAlarm
Metrics
What metrics do I have?
aws cloudwatch list-metrics
Get the Metric
aws cloudwatch get-metric-statistics --metric-name CPUUtilization --namespace AWS/EC2 --dimensions "Name=InstanceId,Value=i-00b9f133ae1a5e033" --statistics Maximum --start-time 2014-04-08T23:18:00 --end-time 2014-04-09T23:18:00 --period 3600
Scenario
sourced from Scenario: Publish Metrics to CloudWatch
Add lots of data
Note: If the metric does not exist CloudWatch creates it
aws cloudwatch put-metric-data --metric-name RequestLatency --namespace GetStarted \
--timestamp 2017-07-14T20:30:00Z --value 87 --unit Milliseconds
aws cloudwatch put-metric-data --metric-name RequestLatency --namespace GetStarted \
--timestamp 2017-07-14T20:30:00Z --value 51 --unit Milliseconds
aws cloudwatch put-metric-data --metric-name RequestLatency --namespace GetStarted \
--timestamp 2017-07-14T20:30:00Z --value 125 --unit Milliseconds
aws cloudwatch put-metric-data --metric-name RequestLatency --namespace GetStarted \
--timestamp 2017-07-14T20:30:00Z --value 235 --unit Milliseconds
aws cloudwatch put-metric-data --metric-name RequestLatency --namespace GetStarted \
--timestamp 2017-07-14T21:30:00Z --statistic-values Sum=577,Minimum=65,Maximum=189,SampleCount=5 --unit Milliseconds
aws cloudwatch put-metric-data --metric-name RequestLatency --namespace GetStarted \
--statistic-values Sum=806,Minimum=47,Maximum=328,SampleCount=6 --unit Milliseconds
Get Metric
aws cloudwatch get-metric-statistics --namespace GetStarted --metric-name RequestLatency --statistics Average \
--start-time 2017-07-13T00:00:00Z --end-time 2017-07-17T00:00:00Z --period 60
There is also a funky CloudWatch Java app… where you can do things like:
mon-put-metric-alarm
mon-enable-alarm
mon-describe-alarms
You can even create an alarm before you have created the metric!!