How this solution works

The Migration Assistant for Amazon OpenSearch Service solution simplifies zero-downtime migrations by capturing, replicating, and replaying traffic between source and target clusters. Client traffic initially flows to the existing source cluster, with an Application Load Balancer directing it to a traffic capture proxy. This proxy forwards traffic to the source while replicating it to Amazon Managed Streaming for Apache Kafka (Amazon MSK) for later replay.

After the traffic capture is active, users initiate a Reindex-from-Snapshot (RFS) process through the Migration Management Console to backfill existing data. After the backfill completes, users employ the Traffic Replayer to synchronize live traffic on the target cluster. Logs and metrics are analyzed to compare the performance and behavior of the source and target clusters, helping ensure that the new setup is functioning as expected. After confirmed, client traffic is redirected to the target cluster, allowing for the safe retirement of the old infrastructure.

This solution supports several scenarios, including metadata migration, backfilling historical data, and replicating live traffic. With tools such as the Traffic Capture Proxy, Traffic Replayer, and Metadata Migration Tool, users can efficiently manage the migration process, helping to ensure that the target environment mirrors the source without disruptions to live services.