Error: dynamodb connection timeout

A connection timeout means the client could not establish a connection in time. A socket timeout or overall function timeout can also involve stalled responses, exhausted connection pools or repeated attempts. Diagnose the failing phase before increasing timeouts.

1. Check DNS, proxy configuration and the actual endpoint from the same runtime or subnet as the application.
2. For a private VPC workload, verify a suitable DynamoDB endpoint or NAT route. Check route tables for gateway endpoints and security groups for interface endpoints.
3. Reuse SDK clients, inspect connection concurrency and throttling, and avoid constructing a fresh HTTP pool for every operation.
4. Set timeouts and retry attempts within the application's total deadline. Retries add network time and backoff, so a per-attempt timeout is not a total request deadline.

import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
import { NodeHttpHandler } from "@smithy/node-http-handler";

const db = new DynamoDBClient({
  maxAttempts: 3,
  requestHandler: new NodeHttpHandler({
    connectionTimeout: 2000,
    socketTimeout: 5000,
  }),
});

These are example values, not DynamoDB defaults. maxAttempts includes the initial attempt. If a write times out after it was sent, it may have committed; verify or use an appropriate condition before replaying a non-idempotent change.

See VPC connectivity and AWS documentation.