Error: DynamoDB stream not working

If a DynamoDB stream appears not to work, determine whether records are being captured or the consumer is failing to read or process them. Check the enabled stream and current ARN first. There is no user-configurable stream buffer to resize.

aws dynamodb describe-table --table-name Orders --region us-east-1 \
  --query 'Table.{Stream:StreamSpecification,Arn:LatestStreamArn}'

1. Confirm a successful item change occurred after the stream was enabled. A no-op write creates no event.
2. Verify that the consumer uses the latest stream ARN and a view type containing the images it expects.
3. For Lambda, inspect the event source mapping, its read permissions, filters, LastProcessingResult, function errors, and IteratorAge.
4. For custom polling, use the DynamoDB Streams client and endpoint, follow shard lineage, and advance to NextShardIterator.
5. Check retention and checkpoint age. Records expire after 24 hours; a consumer cannot fetch an expired backlog.

Custom consumers in a private network also need a route to Streams. DynamoDB Streams supports interface endpoints, not the table gateway endpoint. Lambda’s managed polling is separate from network calls made by your handler. Diagnose these paths separately.

See stream troubleshooting and AWS documentation.