**To find the Amazon DocumentDB instance options you can order** The following ``describe-orderable-db-instance-options`` example lists all instance options for Amazon DocumentDB for a region. :: aws docdb describe-orderable-db-instance-options \ --engine docdb \ --region us-east-1 Output:: { "OrderableDBInstanceOptions": [ { "Vpc": true, "AvailabilityZones": [ { "Name": "us-east-1a" }, { "Name": "us-east-1b" }, { "Name": "us-east-1c" }, { "Name": "us-east-1d" } ], "EngineVersion": "3.6.0", "DBInstanceClass": "db.r4.16xlarge", "LicenseModel": "na", "Engine": "docdb" }, { "Vpc": true, "AvailabilityZones": [ { "Name": "us-east-1a" }, { "Name": "us-east-1b" }, { "Name": "us-east-1c" }, { "Name": "us-east-1d" } } ], "EngineVersion": "3.6.0", "DBInstanceClass": "db.r4.2xlarge", "LicenseModel": "na", "Engine": "docdb" }, { "Vpc": true, "AvailabilityZones": [ { "Name": "us-east-1a" }, { "Name": "us-east-1b" }, { "Name": "us-east-1c" }, { "Name": "us-east-1d" } ], "EngineVersion": "3.6.0", "DBInstanceClass": "db.r4.4xlarge", "LicenseModel": "na", "Engine": "docdb" }, { "Vpc": true, "AvailabilityZones": [ { "Name": "us-east-1a" }, { "Name": "us-east-1b" }, { "Name": "us-east-1c" }, { "Name": "us-east-1d" } ], "EngineVersion": "3.6.0", "DBInstanceClass": "db.r4.8xlarge", "LicenseModel": "na", "Engine": "docdb" }, { "Vpc": true, "AvailabilityZones": [ { "Name": "us-east-1a" }, { "Name": "us-east-1b" }, { "Name": "us-east-1c" }, { "Name": "us-east-1d" } ], "EngineVersion": "3.6.0", "DBInstanceClass": "db.r4.large", "LicenseModel": "na", "Engine": "docdb" }, { "Vpc": true, "AvailabilityZones": [ { "Name": "us-east-1a" }, { "Name": "us-east-1b" }, { "Name": "us-east-1c" }, { "Name": "us-east-1d" } ], "EngineVersion": "3.6.0", "DBInstanceClass": "db.r4.xlarge", "LicenseModel": "na", "Engine": "docdb" } ] } For more information, see `Adding an Amazon DocumentDB Instance to a Cluster <https://docs.aws.amazon.com/documentdb/latest/developerguide/db-instance-add.html>`__ in the *Amazon DocumentDB Developer Guide*.