ElastiCache Migration to Valkey

Opportunity Name: ElastiCache Migration to Valkey

AWS Resource Type: Amazon ElastiCache (Redis OSS Clusters)

Opportunity Description:
This Finder identifies ElastiCache Redis OSS clusters that can be migrated to Valkey 7.2, a new open-source Redis-compatible engine. Valkey offers up to 20% lower pricing, improved multi-core utilization, asynchronous I/O threading, and reduced memory overhead—making it a cost-efficient, high-performance alternative. It is fully compatible with Redis OSS, meaning no application code changes are required for migration.

Criteria for identifying the opportunity:

• Cluster engine is Redis OSS.
• Cluster is active and not tagged with cloudfix_dont_fix_it.
• Estimated annualized cost of Redis cluster ≥ $100.
• Cluster is eligible for Valkey engine switch based on AWS compatibility.
• Pricing savings are calculated at ~20% of current node-based costs.

Potential Savings (range in % on annual basis):

• Estimated average customer savings: ~$6,000 per year.
• Larger enterprise accounts may see savings exceeding $100,000 annually.

What happens when the Fixer is executed?
CloudFix now includes an automated Fixer for this opportunity. The Fixer:

1. If the cluster is a standalone (non-replicated) cache cluster, first converts it into a replication group using the CreateReplicationGroup API, since the engine switch is only supported on replication groups.
2. Reads the cluster's current cache parameter group and creates an equivalent Valkey-compatible parameter group (family valkey7) using the CreateCacheParameterGroup API, copying over any custom (non-default) parameter values.
3. Switches the engine using the ModifyReplicationGroup API with Engine=valkey, EngineVersion=7.2, the new Valkey parameter group, and ApplyImmediately=true.
4. Waits for the replication group to become available, then verifies the engine was switched to Valkey.
5. Applies configuration tags (cloudfix:fixerId, cloudfix:originalResourceId, cloudfix:executionDate) to track the migration.

Note: because standalone cache clusters are converted into replication groups as part of this process, the resource type you see in the AWS console may change even when only one node is involved.

Is it possible to rollback once CloudFix implements the fixer?
 No automated rollback is currently available. Manual reversion to Redis OSS would require cluster recreation or snapshot-based recovery. Customers are advised to validate test environments prior to migration.

Can CloudFix implement the fix automatically once I accept the recommendation?
 Yes. Once approved, CloudFix will automatically execute the migration runbook using AWS SDK and CLI operations.

Does this fix require downtime?
 Minimal or near-zero downtime is expected when AWS zero-downtime migration tools are used. However, testing in pre-production environments is strongly advised before live migration.

Additional Resources:

• Key Considerations in Moving to Valkey on ElastiCache and MemoryDB
• AWS ModifyReplicationGroup API Documentation
• AWS ElastiCache Documentation