Skip to content

Recipe: Add ElastiCache for Redis to Node.js

Prerequisites

  • Running Node.js Elastic Beanstalk environment in a VPC.
  • Amazon ElastiCache for Redis cluster or replication group.
  • Security groups and subnets configured for private connectivity.
  • Node.js Redis client dependency such as ioredis.

What You'll Build

You will connect your Elastic Beanstalk Node.js application to an Amazon ElastiCache for Redis endpoint using environment properties, VPC routing, and security group rules that permit app-to-cache traffic.

flowchart LR
    A[EB EC2 Instance SG] --> B[Redis SG ingress rule]
    A --> C[Node.js app with ioredis]
    C --> D[Redis endpoint from environment property]
    D --> E[Amazon ElastiCache for Redis]

Steps

  1. Provision ElastiCache for Redis in the same VPC as your environment.

  2. Configure security groups.

    • Allow outbound traffic from Elastic Beanstalk instance security group.
    • Allow inbound Redis port traffic to ElastiCache security group from app security group.

  3. Add Redis endpoint values as environment properties.

    REDIS_HOST=<redis-endpoint>
REDIS_PORT=6379

  4. Install and configure ioredis in your Node.js project.

    npm install ioredis

    const Redis = require("ioredis");

const redis = new Redis({
    host: process.env.REDIS_HOST,
    port: Number(process.env.REDIS_PORT || 6379)
});

  5. Add a lightweight cache read or write endpoint for verification.

  6. Deploy and validate Redis operations from application instances.

  7. Protect cache availability with conservative client settings.

    • Set reasonable command timeouts.
    • Limit retry storms during endpoint instability.
    • Handle connection errors without crashing request workers.

  8. Confirm subnet and route alignment.

    • ElastiCache nodes in private subnets.
    • Application instances with network path to cache subnets.
    • No unnecessary public exposure for cache endpoint.

Verification

  • Environment properties expose cache endpoint values to runtime.
  • Application instances establish successful Redis connection.
  • Security group configuration enforces scoped network access.
  • Cache set and get operations succeed through application endpoint.
  • Network and timeout settings support stable runtime behavior.

See Also

Sources