Finest practices for upgrading from Amazon Redshift DC2 to RA3 and Amazon Redshift Serverless

October 16, 2025

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Amazon Redshift is a quick, petabyte-scale cloud information warehouse that makes it easy and cost-effective to research your information utilizing commonplace SQL and your current enterprise intelligence (BI) instruments. Tens of 1000’s of consumers depend on Amazon Redshift to research exabytes of information and run advanced analytical queries, delivering one of the best price-performance.

With a totally managed, AI-powered, massively parallel processing (MPP) structure, Amazon Redshift drives enterprise decision-making rapidly and cost-effectively. Beforehand, Amazon Redshift supplied DC2 (Dense Compute) node sorts optimized for compute-intensive workloads. Nonetheless, they lacked the flexibleness to scale compute and storage independently and didn’t help most of the fashionable options now obtainable. As analytical calls for develop, many purchasers are upgrading from DC2 to RA3 or Amazon Redshift Serverless, which supply unbiased compute and storage scaling, together with superior capabilities reminiscent of information sharing, zero-ETL integration, and built-in synthetic intelligence and machine studying (AI/ML) help with Amazon Redshift ML.

This publish gives a sensible information to plan your goal structure and migration technique, overlaying improve choices, key issues, and greatest practices to facilitate a profitable and seamless transition.

Improve course of from DC2 nodes to RA3 and Redshift Serverless

Step one in direction of improve is to grasp how the brand new structure must be sized; for this, AWS gives a advice desk for provisioned clusters. When figuring out the configuration for Redshift Serverless endpoints, you may assess compute capability particulars by analyzing the connection between RPUs and reminiscence. Every RPU allocates 16 GiB of RAM. To estimate the bottom RPU requirement, divide your DC2 nodes cluster’s whole RAM by 16. These suggestions present steering in sizing the preliminary goal structure however rely upon the computing necessities of your workload. To higher estimate your necessities, contemplate conducting a proof of idea that makes use of Redshift Take a look at Drive to run potential configurations. To be taught extra, see Discover one of the best Amazon Redshift configuration to your workload utilizing Redshift Take a look at Drive and Efficiently conduct a proof of idea in Amazon Redshift. After you determine on the goal configuration and structure, you may construct the technique for upgrading.

Structure patterns

Step one is to outline the goal structure to your answer. You’ll be able to select the principle structure sample that greatest aligns along with your use case from the choices introduced in Structure patterns to optimize Amazon Redshift efficiency at scale. There are two major eventualities, as illustrated within the following diagram.

On the time of writing, Redshift Serverless doesn’t have guide workload administration; every little thing runs with computerized workload administration. Think about isolating your workload into a number of endpoints based mostly on use case to allow unbiased scaling and higher efficiency. For extra data, confer with Structure patterns to optimize Amazon Redshift efficiency at scale.

Improve methods

You’ll be able to select from two attainable improve choices when upgrading from DC2 nodes to RA3 nodes or Redshift Serverless:

Full re-architecture – Step one is to judge and assess the workloads to find out whether or not you may benefit from a contemporary information structure, then re-architect the present platform in the course of the improve course of from DC2 nodes.
Phased method– It is a two-stage technique. The primary stage includes an easy migration to the goal RA3 or Serverless configuration. Within the second stage, you may modernize the goal structure by profiting from cutting-edge Redshift options.

We normally suggest a phased method, which permits for a smoother transition whereas enabling future optimization. The primary stage of a phased method consists of the next steps:

Consider an equal RA3 nodes or Redshift Serverless configuration to your current DC2 cluster, utilizing the sizing tips for provisioned clusters or the compute capability choices for serverless endpoints.
Completely validate the chosen goal configuration in a non-production surroundings utilizing Redshift Take a look at Drive. This automated instrument simplifies the method of simulating your manufacturing workloads on numerous potential goal configurations, enabling a complete what-if evaluation. This step is strongly really helpful.
Proceed to the improve course of when you find yourself happy with the price-performance ratio of a selected goal configuration, utilizing one of many strategies detailed within the following part.

Redshift RA3 cases and Redshift Serverless present entry to highly effective new capabilities, together with zero-ETL, Amazon Redshift Streaming Ingestion, information sharing writes, and unbiased compute and storage scaling. To maximise these advantages, we suggest conducting a complete evaluation of your present structure (the second stage of a phased method) to determine alternatives for modernization utilizing Amazon Redshift’s newest options. For instance:

Improve choices

You’ll be able to select from 3 ways to resize or improve a Redshift cluster from DC2 to RA3 or Redshift Serverless: snapshot restore, basic resize, and elastic resize.

Snapshot restore

The snapshot restore technique follows a sequential course of that begins with capturing a snapshot of your current (supply) cluster. This snapshot is then used to create a brand new goal cluster along with your desired specs. After creation, it’s important to confirm information integrity by confirming that information has been appropriately transferred to the goal cluster. An vital consideration is that any information written to the supply cluster after the preliminary snapshot have to be manually transferred to keep up synchronization.

This technique affords the next benefits:

Permits for the validation of the brand new RA3 or Serverless setup with out affecting the present DC2 cluster
Offers the flexibleness to revive to totally different AWS Areas or Availability Zones
Minimizes cluster downtime for write operations in the course of the transition

Bear in mind the next issues:

Setup and information restore would possibly take longer than elastic resize.
You would possibly encounter information synchronization challenges. Any new information written to the supply cluster after snapshot creation requires guide copying to the goal. This course of would possibly want a number of iterations to realize full synchronization and require downtime earlier than cutoff.
A brand new Redshift endpoint is generated, necessitating connection updates. Think about renaming each clusters so as to keep the unique endpoint (make certain the brand new goal cluster adopts the unique supply cluster’s title)

Basic resize

Amazon Redshift creates a goal cluster and migrates your information and metadata to it from the supply cluster utilizing a backup and restore operation. All of your information, together with database schemas and person configurations, is precisely transferred to the brand new cluster. The supply cluster restarts initially and is unavailable for a couple of minutes, inflicting minimal downtime. It rapidly resumes, permitting each learn and write operations because the resize continues within the background.

Basic resize is a two-stage course of:

Stage 1 (vital path) – Throughout this stage, metadata migration happens between the supply and goal configurations, briefly inserting the supply cluster in read-only mode. This preliminary part is usually transient. When this part is full, the cluster is made obtainable for learn and write queries. Though tables initially configured with KEY distribution model are briefly saved utilizing EVEN distribution, they are going to be redistributed to their unique KEY distribution throughout Stage 2 of the method.
Stage 2 (background operations) – This stage focuses on restoring information to its unique distribution patterns. This operation runs within the background with low precedence with out interfering with the first migration course of. The period of this stage varies based mostly on a number of elements, together with the amount of information being redistributed, ongoing cluster workload, and the goal configuration getting used.

The general resize period is primarily decided by the info quantity being processed. You’ll be able to monitor progress on the Amazon Redshift console or through the use of the SYS_RESTORE_STATE system view, which shows the share accomplished for the desk being transformed (accessing this view requires superuser privileges).

The basic resize method affords the next benefits:

All attainable goal node configurations are supported
A complete reconfiguration of the supply cluster rebalances the info slices to default per node, resulting in even information distribution throughout the nodes

Nonetheless, remember the next:

Stage 2 redistributes the info for optimum efficiency. Nonetheless, Stage 2 runs at a decrease precedence, and in busy clusters, it will probably take a very long time to finish. To hurry up the method, you may manually run the ALTER TABLE DISTSTYLE command in your tables having KEY DISTSTYLE. By executing this command, you may prioritize the info redistribution to occur quicker, mitigating any potential efficiency degradation as a result of ongoing Stage 2 course of.
Because of the Stage 2 background redistribution course of, queries can take longer to finish in the course of the resize operation. Think about enabling concurrency scaling as a mitigation technique.
Drop pointless and unused tables earlier than initiating a resize to hurry up information distribution.
The snapshot used for the resize operation turns into devoted to this operation solely. Due to this fact, it will probably’t be used for a desk restore or different goal.
The cluster should function inside a digital personal cloud (VPC).
This method requires a brand new or a latest guide snapshot taken earlier than initiating a basic resize.
We suggest scheduling the operation throughout off-peak hours or upkeep home windows for minimal enterprise influence.

Elastic resize

When utilizing elastic resize to vary the node sort, Amazon Redshift follows a sequential course of. It begins by making a snapshot of your current cluster, then provisions a brand new goal cluster utilizing the newest information from that snapshot. Whereas information transfers to the brand new cluster within the background, the system stays in read-only mode. Because the resize operation approaches completion, Amazon Redshift mechanically redirects the endpoint to the brand new cluster and stops all connections to the unique one. If any points come up throughout this course of, the system sometimes performs an computerized rollback with out requiring guide intervention, although such failures are uncommon.

Elastic resize affords a number of benefits:

It’s a fast course of that takes 10–quarter-hour on common
Customers keep learn entry to their information in the course of the course of, experiencing solely minimal interruption
The cluster endpoint stays unchanged all through and after the operation

When contemplating this method, remember the next:

Elastic resize operations can solely be carried out on clusters utilizing the EC2-VPC platform. Due to this fact, it’s not obtainable for Redshift Serverless.
The goal node configuration should present adequate storage capability for current information.
Not all goal cluster configurations help elastic resize. In such instances, think about using basic resize or snapshot restore.
After the method is began, elastic resize can’t be stopped.
Information slices stay unchanged; this may probably trigger some information or CPU skew.

Improve suggestions

The next flowchart visually guides the decision-making course of for selecting the suitable Amazon Redshift improve technique.

When upgrading Amazon Redshift, the strategy relies on the goal configuration and operational constraints. For Redshift Serverless, at all times use the snapshot restore technique. If upgrading to an RA3 provisioned cluster, you may select from two choices: use snapshot restore if a full upkeep window with downtime is suitable, or select basic resize for minimal downtime, as a result of it rebalances the info slices to default per node, resulting in even information distribution throughout the nodes. Though you should utilize elastic resize for sure node sort adjustments (for instance, DC2 to RA3) inside particular ranges, it’s not really helpful as a result of elastic resize doesn’t change the variety of slices, probably resulting in information or CPU skew, which might later influence the efficiency of the Redshift cluster. Nonetheless, elastic resize stays the first advice when you’ll want to add or scale back nodes in an current cluster.

Finest practices for migration

When planning your migration, contemplate the next greatest practices:

Conduct a pre-migration evaluation utilizing Amazon Redshift Advisor or Amazon CloudWatch.
Select the best goal structure based mostly in your use instances and workloads. You should use Redshift Take a look at Drive to find out the best goal structure.
Backup utilizing guide snapshots, and allow automated rollback.
Talk timelines, downtime, and adjustments to stakeholders.
Replace runbooks with new structure particulars and endpoints.
Validate workloads utilizing benchmarks and information checksum.
Use upkeep home windows for ultimate syncs and cutovers.

By following these practices, you may obtain a managed, low-risk migration that balances efficiency, value, and operational continuity.

Conclusion

Migrating from Redshift DC2 nodes to RA3 nodes or Redshift Serverless requires a structured method to help efficiency, cost-efficiency, and minimal disruption. By choosing the best structure to your workload, and validating information and workloads post-migration, organizations can seamlessly modernize their information platforms. This improve facilitates long-term success, serving to groups totally harness RA3’s scalable storage or Redshift Serverless auto scaling capabilities whereas optimizing prices and efficiency.