ElastiCache for Redis and Application Auto Scaling - Application Auto Scaling

ElastiCache for Redis and Application Auto Scaling

You can scale ElastiCache for Redis replication groups using target tracking scaling policies and scheduled scaling.

Use the following information to help you integrate ElastiCache with Application Auto Scaling.

If you are just getting started with scaling ElastiCache for Redis replication groups, you can view sample configurations and details about using ElastiCache with Application Auto Scaling in the following documentation:

Service-linked role created for ElastiCache

The following service-linked role is automatically created in your AWS account when registering ElastiCache resources as scalable targets with Application Auto Scaling. This role allows Application Auto Scaling to perform supported operations within your account. For more information, see Service-linked roles for Application Auto Scaling.

  • AWSServiceRoleForApplicationAutoScaling_ElastiCacheRG

Service principal used by the service-linked role

The service-linked role in the previous section can be assumed only by the service principal authorized by the trust relationships defined for the role. The service-linked role used by Application Auto Scaling grants access to the following service principal:

  • elasticache.application-autoscaling.amazonaws.com

Registering ElastiCache for Redis replication groups as scalable targets with Application Auto Scaling

Application Auto Scaling requires a scalable target before you can create scaling policies or scheduled actions for an ElastiCache replication group. A scalable target is a resource that Application Auto Scaling can scale out and scale in. Scalable targets are uniquely identified by the combination of resource ID, scalable dimension, and namespace.

If you configure auto scaling using the ElastiCache console, then ElastiCache automatically registers a scalable target for you.

If you want to configure auto scaling using the AWS CLI or one of the AWS SDKs, you can use the following options:

  • AWS CLI:

    Call the register-scalable-target command for an ElastiCache replication group. The following example registers the desired number of node groups for a replication group called mycluster, with a minimum capacity of one and a maximum capacity of five.

    aws application-autoscaling register-scalable-target \ --service-namespace elasticache \ --scalable-dimension elasticache:replication-group:NodeGroups \ --resource-id replication-group/mycluster \ --min-capacity 1 \ --max-capacity 5

    The following example registers the desired number of replicas per node group for a replication group called mycluster, with a minimum capacity of 1 and a maximum capacity of 5.

    aws application-autoscaling register-scalable-target \ --service-namespace elasticache \ --scalable-dimension elasticache:replication-group:Replicas \ --resource-id replication-group/mycluster \ --min-capacity 1 \ --max-capacity 5
  • AWS SDK:

    Call the RegisterScalableTarget operation and provide ResourceId, ScalableDimension, ServiceNamespace, MinCapacity, and MaxCapacity as parameters.