Use a pool

To reduce cluster start time, you can attach a cluster to a predefined pool of idle instances. When attached to a pool, a cluster allocates its driver and worker nodes from the pool. If the pool does not have sufficient idle resources to accommodate the cluster’s request, the pool expands by allocating new instances from the instance provider. When an attached cluster is terminated, the instances it used are returned to the pool and can be reused by a different cluster.


  • You must have permission to attach to the pool; see Pool access control.

  • You must add the following permissions to the access policy associated with the cross-account IAM role or keys used to create your AWS account:

      "Action": [

    For the complete list of permissions and instructions on how to update your existing cross-account IAM role or keys, see Configure your AWS account (cross-account IAM role) or contact your internal Databricks administrator.


    If you do not add these permissions, you will not be able to start the cluster.

Attach a cluster to a pool

To attach a cluster to a pool, select the pool in the Pool drop-down.

Select pool

Inherited configuration

When a cluster is attached to a pool, the following configuration properties are inherited from the pool:

  • Cluster node type: You cannot select separate driver and worker node types.
  • Custom Cluster Tags: You can add additional custom tags for the cluster, and both the cluster-level tags and those inherited from the pool will be applied. You cannot add a cluster-specific custom tag with the same key name as a custom tag inherited from a pool (that is, you cannot override a custom tag that is inherited from the pool).
  • AWS configurations: Apart from Configure clusters, these cannot be modified at the cluster level.