Amazon Redshift has launched the ability to run a single-node RA3.xlplus cluster. Amazon Redshift RA3 clusters support many important features including Amazon Redshift Managed Storage (RMS), data sharing and AQUA. Single-node RA3.xlplus clusters allow you to take advantage of the most advanced Redshift features at a lower cost. You can migrate single-node DS2.xlarge or single-node DC2.large clusters to single-node RA3.xlplus clusters as part of a cross-instance Classic Resize function. You can also use cross-instance Classic Resize as part of the Reserved Instance (RI) Migration feature in the Amazon Redshift Console, CLI or API to migrate your single-node DS2.xlarge RI clusters to RA3.xlplus RI clusters without changes to the RI contract’s start or end dates and without incurring additional charges.
Source:: Amazon AWS