I have a load balancer that I created an auto-scaling-group and launch-config for. I created the auto-scaling-group with a min-size of 1 and max size of 20. I have a scaledown policy:
as-put-scaling-policy SBMScaleDownPolicy --auto-scaling-group SBMAutoScaleGroup --adjustment=-1 --type ChangeInCapacity --cooldown 300
Then I set up an alarm:
mon-put-metric-alarm SBMLowCPUAlarm --comparison-operator LessThanThreshold --evaluation-periods 1 --metric-name CPUUtilization --namespace "AWS/EC2" --period 600 --statistic Average --threshold 35 --alarm-actions arn:aws:autoscaling:us-east-1:policystuffhere:autoScalingGroupName/SBMAutoScaleGroup:policyName/SBMScaleDownPolicy --dimensions "AutoScalingGroupName=SBMAutoScaleGroup"
When average CPU usage over 10 minutes is under 35, in CloudFront the alarm shows up as "In Alarm State" but doesn't decrease the number of instances. Also, if there's only one instance running it'll spin up another to 2 even if a scale up alarm isn't hit. It seems like the default value is just set to 2 somehow. How can I change this?