How to reindex in OpenSearch?

Reindexing in OpenSearch is a useful feature that allows you to create a new version of your index with different configurations or consolidate data from multiple indices. This guide provides step-by-step instructions on how to reindex your data within the Logit.io-managed OpenSearch service.

Prerequisites

Active Logit.io account (opens in a new tab) with OpenSearch service enabled.
Familiarity with Logit.io's OpenSearch Dashboards.
Basic understanding of JSON and OpenSearch DSL (Domain Specific Language).

Step 1: Access the OpenSearch Dashboard

Navigate to the OpenSearch Dashboards by clicking Launch Logs.

Select the environment that contains your indices, if applicable.

Step 2: Open Dev Tools

The Dev Tools option in Logit.io's OpenSearch Dashboards allows you to directly execute OpenSearch API commands.

Find and click on "Dev Tools" in the left-hand navigation menu.

Prepare to enter your reindex command in the console.

Step 3: Plan Your Reindex Operation

Before executing the reindex command, decide on the following:

Source index: The index (or indices) you're reindexing from.

Destination index: The new index you're creating. If it doesn't exist, OpenSearch will automatically create it during the reindexing process.

Reindex script (optional): Any transformations you wish to apply to your documents during reindexing.

Step 4: Execute the Reindex Command

In the Dev Tools console, use the reindex API to start the process. Below is a basic template for reindexing:

POST /_reindex
{
  "source": {
    "index": "source_index_name"
  },
  "dest": {
    "index": "destination_index_name"
  }
}

Replace source_index_name with the name of your current index and destination_index_name with the name of your new index.

If you need to apply transformations or conditions, refer to the OpenSearch documentation for the script field in the reindex API.

Step 5: Monitor the Reindex Operation

Reindexing can take time depending on the size of your indices and the complexity of any scripts you're using. You can monitor progress through the OpenSearch Dashboards.

Step 6: Verify the Reindex

After the reindex operation completes, verify that the documents are correctly copied to your destination index:

GET /destination_index_name/_count

This command returns the count of documents in the destination index. Ensure this matches your expectations based on the source index.

Troubleshooting

Failed reindexing: Check the OpenSearch logs for errors. Common issues include scripting errors or resource limitations.

Performance issues: Large reindex operations can impact cluster performance. Consider performing reindexing during off-peak hours.

By following these steps, you can efficiently reindex your data within the Logit.io platform, ensuring your indices are configured for optimal performance and relevance.

For more complex reindexing needs or troubleshooting feel free to reach out to the Logit.io support team for personalized assistance.

List Indexes OpenSearch Dashboards