Redis Licensing Change: What AWS Customers Need to Know

The open-source world has been rocked recently. Redis, the popular in-memory data store, abandoned its open-source licensing model for a more restrictive dual-license. This shift from the permissive BSD license to the Redis Source Available License (RSAL) and MongoDB's Server Side Public License (SSPL) has major implications for developers and cloud providers alike.

The licensing change was driven by Redis Labs' frustrations that large cloud providers were repackaging their open-source software into proprietary services without providing enough value back to the community. While cloud giants like AWS, Microsoft, and Google have greatly benefited from open-source software, there is an ongoing debate about their level of contribution and support.

This blog post dives into the impact of this change on AWS customers, AWS’s recent response, and other Redis alternatives.

What is the Impact on AWS Customers?

For AWS customers, Redis' licensing change could have major ramifications depending on how they are utilizing the data store. It's important to thoroughly evaluate your Redis usage and decide if a migration to an alternative is necessary.

Here are the key areas where customers may be impacted:

Application Usage

If you have built applications using the open-source Redis, the licensing change limits your ability to use future versions of Redis without complying with their new restrictive licenses. You essentially have three options:

a) Pin to an older, open-source version of Redis and miss out on future updates/bugfixes

b) Re-license your application under SSPL, which places restrictions on how you can use/distribute it

c) Migrate to an open-source alternative like Valkey, Redict, or others

Remaining on the existing Redis version long-term is risky, while re-licensing under SSPL may limit redistribution. Migrating to Valkey or another open fork provides continuity.

ElastiCache for Redis

AWS offers a managed Redis service called ElastiCache for Redis. This allows customers to run Redis cluster deployments on AWS infrastructure without having to self-manage the Redis software and instances.

For customers utilizing ElastiCache for Redis, the licensing changes by Redis Labs create several areas of uncertainty and potential impacts:

Pricing Changes

Currently, ElastiCache pricing is based on factors like instance types and data transfer. However, with Redis now requiring a paid license for cloud providers, AWS may need to adjust ElastiCache pricing to account for these new costs from Redis Labs. Higher pricing could be passed on to ElastiCache customers.

Forced Migration

Rather than pay the new Redis fees, AWS may choose to migrate the entire ElastiCache Redis service to an open-source alternative, like Valkey. This would avoid licensing costs but force customers to transition to the new Redis-compatible data store.

Service Disruption

Even if AWS continues offering Redis under the new licensing terms initially, there could be service disruptions as they navigate the licensing changes. This includes being locked out of future Redis updates/patches from the upstream project.

The path forward for ElastiCache for Redis is uncertain. AWS has not yet publicly communicated their plans, leaving customers wondering if they should begin exploring migration to self-managed open-source alternatives themselves.

Customers running Redis clusters on ElastiCache should:

• Review AWS communications on pricing/product updates
• Evaluate the implications if AWS does force a Valkey or similar migration
• Understand requirements to self-manage open-source Redis if needed
• Explore other AWS or self-managed data store alternatives

For enterprises heavily reliant on ElastiCache Redis, proactive evaluation and planning for various scenarios is critical. Having a contingency migration plan can avoid battling disruptive changes.

Redistribution Concerns

Even if you run Redis on-premises or on other clouds, the licensing changes create legal risks around how you redistribute binaries or source code incorporating Redis. Migration avoids this intellectual property minefield.

Under the previous BSD license, developers had broad freedom to incorporate Redis into their applications or products and redistribute that combined software with few restrictions.

However, the new Redis Source Available License (RSAL) and Server Side Public License (SSPL) place strict limitations on redistribution, especially in the context of providing Redis as a service or bundling it into a product.

For AWS customers building applications that incorporate or extend Redis, these are the key areas of concern:

Combined Work Licensing

Any combined work distributing the RSAL/SSPL code must also be licensed under SSPL. This could force you to re-license your proprietary application using Redis under these restrictive copyleft-style terms.

Redistribution Lockout 

The licenses may prevent you from redistributing static or dynamic Redis binaries with your application at all without a commercial license from Redis Labs.

Compliance Obligations

Even if allowed, redistributing Redis code creates complex compliance obligations around providing source code and abiding by specifications of the SSPL.

These issues put AWS customers using Redis to build products or extend them with proprietary code at legal risk. You may be unintentionally creating a situation of non-compliance with the new license terms through redistribution.

As a starting point, you should ask yourself: do you distribute Redis as part of a deliverable? Do you provide Redis as a service? If the answer is no, then you likely need not be concerned beyond the possible migration effects of the AWS decision. These two questions are not a be-all and end-all to this discussion, though. While the simplest path to avoid issues is to migrate away from incorporating RSAL/SSPL licensed Redis versions, we recommend discussing this with your legal counsel.

Open Source Philosophy

For customers deeply committed to open source values like software freedom, redistributability, and community-driven development, the Redis license change is antithetical. Projects like Valkey better align with these principles.

Evaluating your Redis usage, legal/licensing impacts, and philosophical alignment with open source is critical. AWS customers may need to make tough decisions to preserve their software supply chain integrity. Migrations take considerable time/resources, so starting the process as soon as possible is advisable.

AWS's Response: Backing the Valkey Fork

In the wake of Redis' decision, AWS has thrown its considerable weight behind Valkey, a community-driven fork of the Redis project. Valkey is being developed by former Redis maintainers like Madelyn Olson, an AWS employee who has worked on Redis for six years.

Along with AWS and Google Cloud, the Linux Foundation is overseeing Valkey, which will be licensed under the permissive BSD 3-clause license. This ensures Valkey remains open source and freely available for use and modification by anyone.

The creation of Valkey demonstrates AWS's commitment to supporting open-source projects and communities. After being criticized in the past for "open source strip mining," AWS is now taking a leading role in sustaining a libre Redis alternative.

Other Redis Alternatives

While Valkey has major cloud provider backing, other Redis forks are also emerging:

• Redict by Drew DeVault aims to be a completely FOSS, community-driven project under the LGPL license.
• MemVerge has created MemRedit, claiming better performance than standard Redis.

These exemplify the power of open source – when a project makes controversial changes, the code can be forked to preserve the original vision.

Next Steps

For AWS customers committed to open source, this Redis disruption is both a challenge and an opportunity. Evaluating alternatives like Valkey allows migration to solutions that are better aligned with your values. Additionally, the vigorous community response demonstrates the power of open source in sustaining software freedom.

No matter which path you choose, the changes with Redis make it an ideal time to review your architecture's data store dependencies. An AWS Premier Tier Services Partner like Mission Cloud can also help you determine your next steps. As open source continues redefining its relationship with cloud providers, make sure you have a sustainable strategy firmly planted on the principles you believe in.