rightsize_elasticache

AWS Rightsize ElastiCache

What It Does

This policy template reports any underutilized AWS ElastiCache resources based on CPU and memory usage. Optionally, this report can be emailed and oversized resources can be downsized.

Policy Savings Details

The policy includes the estimated monthly savings. The estimated monthly savings is recognized if the resource is downsized.

• The Estimated Monthly Savings is calculated by multiplying the amortized cost of the resource for 1 day, as found within Flexera CCO, by 30.44, which is the average number of days in a month.
• Savings is estimated as the difference of the current cost of the resource and the estimated cost of the recommended resource type.
• Since the costs of individual resources are obtained from Flexera CCO, they will take into account any Flexera adjustment rules or cloud provider discounts present in the Flexera platform.
• If the resource cannot be found in Flexera CCO, the Estimated Monthly Savings is 0.
• The incident message detail includes the sum of each resource Estimated Monthly Savings as Potential Monthly Savings.
• Both Estimated Monthly Savings and Potential Monthly Savings will be reported in the currency of the Flexera organization the policy is applied in.

Input Parameters

• Email Addresses - Email addresses of the recipients you wish to notify when new incidents are created.
• Account Number - The Account number for use with the AWS STS Cross Account Role. Leave blank when using AWS IAM Access key and secret. It only needs to be passed when the desired AWS account is different than the one associated with the Flexera One credential. More information is available in our documentation.
• Allow/Deny Regions - Whether to treat Allow/Deny Regions List parameter as allow or deny list. Has no effect if Allow/Deny Regions List is left empty.
• Allow/Deny Regions List - A list of regions to allow or deny for an AWS account. Please enter the regions code if SCP is enabled. See Available Regions in AWS; otherwise, the policy may fail on regions that are disabled via SCP. Leave blank to consider all the regions.
• Exclusion Tags - The policy will filter resources containing the specified tags from the results. The following formats are supported:
  • Key - Filter all resources with the specified tag key.
  • Key==Value - Filter all resources with the specified tag key:value pair.
  • Key!=Value - Filter all resources missing the specified tag key:value pair. This will also filter all resources missing the specified tag key.
  • Key=~/Regex/ - Filter all resources where the value for the specified key matches the specified regex string.
  • Key!~/Regex/ - Filter all resources where the value for the specified key does not match the specified regex string. This will also filter all resources missing the specified tag key.
• Exclusion Tags: Any / All - Whether to filter instances containing any of the specified tags or only those that contain all of them. Only applicable if more than one value is entered in the Exclusion Tags field.
• Skip Instance Sizes - Whether to recommend downsizing multiple sizes. When set to 'No', only the next smaller size will ever be recommended for downsizing. When set to 'Yes', more aggressive downsizing recommendations will be made when appropriate.
• Statistic Lookback Period - How many days back to look at CPU and memory usage data for clusters. This value cannot be set higher than 90 because AWS does not retain metrics for longer than 90 days.
• Threshold Statistic - Statistic to use when determining if a cluster is underutilized.
• CPU Threshold (%) - The CPU threshold at which to consider a cluster to be 'underutilized' and therefore be flagged for downsizing. Set to -1 to ignore CPU utilization
• Freeable Memory Threshold (%) - The freeable memory threshold at which to consider a cluster to be 'underutilized' and therefore be flagged for downsizing. Set to -1 to ignore memory utilization
• Automatic Actions - When this value is set, this policy will automatically take the selected action(s).

Please note that the "Automatic Actions" parameter contains a list of action(s) that can be performed on the resources. When it is selected, the policy will automatically execute the corresponding action on the data that failed the checks, post incident generation. Please leave this parameter blank for manual action. For example if a user selects the "Downsize ElastiCache Nodes" action while applying the policy, the nodes of all underutilized ElastiCache clusters will be downsized.

Policy Actions

• Sends an email notification
• Downsize nodes of underutilized ElastiCache clusters after approval

Prerequisites

This Policy Template uses Credentials for authenticating to datasources -- in order to apply this policy you must have a Credential registered in the system that is compatible with this policy. If there are no Credentials listed when you apply the policy, please contact your Flexera Org Admin and ask them to register a Credential that is compatible with this policy. The information below should be consulted when creating the credential(s).

Credential configuration

For administrators creating and managing credentials to use with this policy, the following information is needed:

• AWS Credential (provider=aws) which has the following permissions:

  • sts:GetCallerIdentity
  • cloudwatch:GetMetricData
  • ec2:DescribeRegions
  • elasticache:DescribeCacheClusters
  • elasticache:ListTagsForResource
  • elasticache:ModifyCacheCluster*

  * Only required for taking action (terminating or downsizing); the policy will still function in a read-only capacity without these permissions.

  Example IAM Permission Policy:

  {
      "Version": "2012-10-17",
      "Statement": [
          {
              "Effect": "Allow",
              "Action": [
                  "sts:GetCallerIdentity",
                  "cloudwatch:GetMetricData",
                  "ec2:DescribeRegions",
                  "elasticache:DescribeCacheClusters",
                  "elasticache:ListTagsForResource",
                  "elasticache:ModifyCacheCluster"
              ],
              "Resource": "*"
          }
      ]
  }

• Flexera Credential (provider=flexera) which has the following roles:

  • billing_center_viewer

The Provider-Specific Credentials page in the docs has detailed instructions for setting up Credentials for the most common providers.

Supported Clouds

• AWS

Cost

This policy template does not incur any cloud costs.