Today we’re announcing enhancements to Amazon ElastiCache Reserved Nodes that make them flexible and easier to use, helping you get the most out of your reserved nodes discount. Reserved nodes provide you with a significant discount compared to on-demand node prices, enabling you to optimize costs based on your expected usage.
Previously, you needed to purchase a reservation for a specified node type (e.g. cache.r7g.xlarge) and would only be eligible for a discount on the given type with no flexibility. With this feature, ElastiCache reserved nodes offer size flexibility within an instance family (or node family) and AWS region. This means that your existing discounted reserved node rate will be applied automatically to usage of all sizes in the same node family. For example, if you purchase a r7g.xlarge reserved node and need to scale to a larger node such as r7g.2xlarge, your reserved node discounted rate is automatically applied to 50% usage of the r7g.2xlarge node in the same AWS Region. The size flexibility capability will reduce the time that you need to spend managing your reserved nodes. With this feature, you can get the most out of your discount even if your capacity needs change.
Amazon ElastiCache reserved node size flexibility is available in all AWS Regions, including the AWS GovCloud (US) Regions and China Regions. To learn more, visit Amazon ElastiCache, the ElastiCache user guides and our blog post.
Source:: Amazon AWS