aws_create_scaling_policies.sh

#!/bin/bash
set -x verbose

########################
# Create scaling policy
########################

AUTOSCALING_GROUP="app-autoscaling-group"
TYPE="ChangeInCapacity"
COOLDOWN=300

# Policy function
function add_policy(){
  local RSLT=`as-put-scaling-policy \
    --auto-scaling-group $AUTOSCALING_GROUP \
    --name $POLICY_NAME \
    "--adjustment=$ADJUSTMENT" \
    --type $TYPE \
    --cooldown $COOLDOWN`
  echo $RSLT
}

echo "scale up policy"
POLICY_NAME="scale-up"
ADJUSTMENT=1
SCALE_UP=$(add_policy)

echo "scale down policy"
POLICY_NAME="scale-down"
ADJUSTMENT="-1"
SCALE_DOWN=$(add_policy)

########################
# Create scaling alarms
########################

METRIC_NAME="CPUUtilization"
NAMESPACE="AWS/EC2"
STATISTIC="Average"
PERIOD="60"
DIMENSIONS="AutoScalingGroupName=$AUTOSCALING_GROUP"
EVAL_PERIODS=3
UNIT="Percent"

function add_alarm(){
  local RSLT=`mon-put-metric-alarm --alarm-name $ALARM_NAME \
    --alarm-description $ALARM_DESC \
    --metric-name $METRIC_NAME \
    --namespace $NAMESPACE \
    --statistic $STATISTIC \
    --period $PERIOD \
    --threshold $THRESHOLD \
    --comparison-operator $COMPARISON_OPERATOR \
    --dimensions $DIMENSIONS \
    --evaluation-periods $EVAL_PERIODS \
    --unit $UNIT \
    --alarm-actions $ALARM_ACTION`
  echo $RSLT
}

echo "adding scale up alarm"
ALARM_NAME="app-scale-up"
THRESHOLD=70
ALARM_DESC="Scale-up-at-$THRESHOLD-percent-load"
COMPARISON_OPERATOR="GreaterThanThreshold"
ALARM_ACTION=$SCALE_UP

add_alarm

echo "adding scale down alarm"
ALARM_NAME="app-scale-down"
THRESHOLD=15
ALARM_DESC="Scale-down-at-$THRESHOLD-percent-load"
COMPARISON_OPERATOR="LessThanThreshold"
ALARM_ACTION=$SCALE_DOWN

add_alarm