# Creating collections
<a name="serverless-create"></a>

You can use the console or the AWS CLI to create a serverless collection. These steps cover how to create a *search* or *time series* collection. To create a *vector search* collection, see [Working with vector search collections](serverless-vector-search.md). 

Before you create a collection, ensure that you have the required permissions. For more information, see [Configuring permissions for collections](serverless-collection-permissions.md).

Amazon OpenSearch Serverless supports two collection generations:
+ **NextGen** – The latest generation of OpenSearch Serverless with instant auto scaling and scale-to-zero for cost optimization. Uses collection groups for shared capacity management across multiple collections. Offers a simplified single-page creation flow with Express Create and Standard Create options.
+ **Classic** – Uses a multi-step wizard with per-collection security, network, and encryption configuration. Each collection is configured independently.

When you choose **Create collection** from the Collections page, the console opens the **NextGen** creation form by default. You can switch between generations at any time using the **Switch to Classic** or **Switch to NextGen** link in the **Serverless generation** field on the creation form.
+ [Create a NextGen collection (Express Create)](#serverless-create-nextgen-easy)
+ [Create a NextGen collection (Standard Create)](#serverless-create-nextgen-standard)
+ [Create a Classic collection](#serverless-create-classic)
+ [Configure collection settings (Classic)](#serverless-create-console-step-2)
+ [Configure additional search fields (Classic)](#serverless-create-console-step-3)

## Configure NextGen collection settings
<a name="serverless-create-nextgen-settings"></a>

The following steps are common to both Express Create and Standard Create methods.

**To configure NextGen collection settings**

1. Navigate to the Amazon OpenSearch Service console at [https://console.aws.amazon.com/aos/home/](https://console.aws.amazon.com/aos/home/).

1. Expand **Serverless** in the left navigation pane and choose **Collections**.

1. Choose **Create collection**. The NextGen collection creation form appears by default.
**Tip**  
To create a Classic collection instead, choose **Switch to Classic** in the **Serverless generation** field.

1. Provide a name and description for the collection. The name must meet the following criteria:
   + Is unique to your account and AWS Region
   + Contains only lowercase letters a-z, the numbers 0–9, and the hyphen (-)
   + Contains between 3 and 32 characters

1. Choose a collection type:
   + **Search** – Full-text search that powers applications in your internal networks and internet-facing applications. All search data is stored in hot storage to ensure fast query response times.
   + **Vector search** – Semantic search on vector embeddings that simplifies vector data management. Powers machine learning (ML) augmented search experiences and generative AI applications.

   For more information, see [Choosing a collection type](serverless-overview.md#serverless-usecase).

1. Choose a collection creation method: **Express Create** or **Standard Create**.

## Create a NextGen collection (Express Create)
<a name="serverless-create-nextgen-easy"></a>

Express Create lets you quickly set up a NextGen collection with sensible defaults. OpenSearch Serverless automatically creates the required collection group, encryption, network, and data access policies for you based on the collection name and collection type you provide.

**Note**  
You can also access Express Create from:  
The **Express create** button in the blue info banner on the Amazon OpenSearch Service landing page
The **Express create** button on the Get Started Quick Create card
Both open an Express Create modal directly without navigating to the full create page.

When you use Express Create from the modal, you can create a collection in seconds without navigating to the full create collection form. Enter a collection name, choose a collection type (**Search** or **Vector search**), and choose **Create collection**. OpenSearch Serverless automatically configures the remaining settings with sensible defaults.

You can expand the **Configuration details** section to review or modify settings such as collection group, OpenSearch UI settings, encryption, network access, and data access before creating the collection. Some settings can also be changed after creation.

**To create a NextGen collection using Express Create**

1. After configuring the collection name, description, and type (see [Configure NextGen collection settings](#serverless-create-nextgen-settings)), choose **Express Create** as the collection creation method.

1. Review the default settings table that OpenSearch Serverless configures on your behalf:
   + **Collection group** – For a first-time user, a default collection group name is auto-generated based on the collection name. You can edit the name by choosing the edit icon. For a returning user, existing NextGen collection groups of the selected type are displayed. One is selected by default. You can select any other existing collection group from the dropdown.
   + **OpenSearch UI settings** – Uses an existing OpenSearch application by default. The application name and workspace name are editable after creation.
   + **Encryption** – The collection is encrypted with an AWS owned key.
   + **Network access** – The collection is accessible from public networks.
   + **Data access** – A data access policy is automatically created that grants the current IAM principal full access to the collection and its indexes.

1. Choose **Create collection**.

The collection status shows `Creating`. Wait for the collection status to change to `Active` before you begin indexing data. This typically takes several minutes.

## Create a NextGen collection (Standard Create)
<a name="serverless-create-nextgen-standard"></a>

Standard Create gives you full control over collection group, encryption, network, and data access configuration.

**To create a NextGen collection using Standard Create**

1. Follow steps 1–5 from [Configure NextGen collection settings](#serverless-create-nextgen-settings).

1. Under **Collection creation method**, select **Standard create**.

   The form expands to show the full configuration sections described in the following sections.

### Configure collection group
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Choose how to assign a collection group. You can select an existing compatible group or create a new one, even if compatible groups already exist.
+ **Select existing** – Choose a compatible collection group from the dropdown. The group must support your selected collection type. The console displays the group's current capacity limits (min/max OCU for indexing and search).
+ **Create new** – Create a new collection group with custom capacity limits:
  + **Collection group name** – Auto-generated as `nextgen-{collection-name}`. You can edit this name. The name is normalized to lowercase, hyphens replace underscores, and it is truncated to 32 characters.
  + **Min Indexing Capacity** (in OCUs) – Optional. Leave blank for no minimum.
  + **Max Indexing Capacity** (in OCUs) – Default is 96.
  + **Min Search Capacity** (in OCUs) – Optional. Leave blank for no minimum.
  + **Max Search Capacity** (in OCUs) – Default is 96.

### Configure encryption
<a name="serverless-create-nextgen-standard-encryption"></a>

Choose an encryption option:
+ **Use AWS owned key** (default) – Amazon OpenSearch Service manages the encryption key at no additional cost.
+ **Use customer managed key** – Select a AWS KMS key from your account.

(Optional) Select the **Customize encryption settings** checkbox to choose or create a different AWS KMS key.

For more information about encryption policies, see [Encryption in Amazon OpenSearch Serverless](serverless-encryption.md).

### Configure network access
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Configure network access for your collection:
+ Enable or disable **public access** to the OpenSearch endpoint.
+ (Optional) Add VPC endpoint rules to restrict access.

### Configure data access policy
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Choose how to configure data access:
+ **Create new policy** – Define a new data access policy:
  + Enter a **policy name** and optional **description**.
  + Use the **visual editor** to add statements with principals and resource permissions, or switch to the **JSON editor** for direct policy editing.
  + Add principals: IAM users and roles, SAML users and groups, or users and groups.
  + Specify resource permissions for collections and indexes.
+ **Add to existing policy** – Select an existing data access policy from the dropdown.

### Configure additional settings
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+ (Optional) Add **tags** to your collection as key-value pairs.

### Configure OpenSearch UI settings
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Configure the OpenSearch application and workspace for your collection:
+ For **OpenSearch application selection**, choose one of the following:
  + **Select existing OpenSearch application** – Choose an existing application from the **OpenSearch application name** dropdown. Then for **Workspace selection**, choose **Select existing workspace** or **Create new workspace** and enter a name.
  + **Create new OpenSearch application** – Enter a name for the new application. You must also create a new workspace – enter a name for the workspace.

To create the collection, review your configuration and choose **Submit**.

After you submit, the collection enters a **Creating** status. The console also creates the collection group (if new), encryption policy, network policy, and data access policy as needed. When the collection status changes to **Active**, it is ready to use. This typically takes several minutes.

## Create a Classic collection
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Classic collections use a multi-step wizard with per-collection security, network, and encryption configuration. Each collection is configured independently.

### Configure collection settings (Classic)
<a name="serverless-create-console-step-2"></a>

**To configure basic collection settings (Classic)**

1. Navigate to the Amazon OpenSearch Service console at [https://console.aws.amazon.com/aos/home/](https://console.aws.amazon.com/aos/home/). In the left navigation pane, expand **Serverless** and choose **Collections**.

1. Choose **Create collection**.

   The console opens the **Create NextGen collection** form by default.

1. In the **Serverless generation** field, choose **Switch to Classic**.

   The console navigates to the Classic collection creation wizard. The **Serverless generation** field now displays **Classic** with a description: *This is the Classic collections create flow.*
**Tip**  
To switch back to NextGen, choose **Switch to NextGen** in the **Serverless generation** field.

1. Provide a **name** and **description** for the collection. The name must meet the following criteria:
   + Is unique to your account and AWS Region
   + Contains only lowercase letters a–z, the numbers 0–9, and the hyphen (-)
   + Contains between 3 and 32 characters

1. Choose a **collection type**:
   + **Time series** – Log analytics segment that focuses on analyzing large volumes of semi-structured, machine-generated data. At least 24 hours of data is stored on hot indexes, and the rest remains in warm storage.
   + **Search** – Full-text search that powers applications in your internal networks and internet-facing applications. All search data is stored in hot storage to ensure fast query response times. Choose this option if you are enabling automatic semantic search.
   + **Vector search** – Semantic search on vector embeddings that simplifies the management of vector data. Powers machine learning (ML) augmented search experiences and generative AI applications such as chatbots, personal assistants, and fraud detection.

1. (Optional) Configure **deployment options**:
   + **Standby replicas** – Choose whether to enable standby replicas for high availability.
   + **GPU acceleration** – For vector search collections, choose whether to enable GPU acceleration.

1. Choose **Next**.

**To configure security and access policies (Classic)**

1. **Encryption policy** – Choose how to encrypt data in your collection:
   + **Use AWS owned key** (default) – Amazon OpenSearch Service manages the encryption key at no additional cost.
   + **Use customer managed key** – Select a AWS KMS key from your account for encryption.

   (Optional) Select **Use existing policy** if a matching encryption policy already exists for your collection name.

1. **Network access** – Configure how users and applications access your collection:
   + Enable or disable **access to OpenSearch endpoint**.
   + Enable or disable **access to OpenSearch Dashboards **.
   + Choose **Public** access or restrict access through **VPC endpoints**.

1. **Data access policy** – Define which principals can access your collection's data:
   + **Create new policy** – Define a new data access policy using the visual editor or JSON editor. Add principals (IAM users, IAM roles, or SAML users and groups) and specify resource permissions.
   + **Add to existing policy** – Select an existing data access policy from the dropdown.

1. Choose **Next**.

### Configure OpenSearch UI (Classic)
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Configure the OpenSearch application and workspace for your collection:
+ For **OpenSearch application selection**, choose one of the following:
  + **Select existing OpenSearch application** – Choose an existing application from the **OpenSearch application name** dropdown. Then for **Workspace selection**, choose **Select existing workspace** or **Create new workspace** and enter a name.
  + **Create new OpenSearch application** – Enter a name for the new application. You must also create a new workspace – enter a name for the workspace.

Choose **Next**.

### Configure additional search fields (Classic)
<a name="serverless-create-console-step-3"></a>

The options you see on this page depend on the type of collection you are creating.
+ **Search collections** – Configure automatic semantic enrichment and lexical search fields.
+ **Time series collections** – Configure time series search fields.
+ **Vector search collections** – Configure vector fields, including field name, dimensions, and distance metric.

(Optional) Configure the search fields relevant to your collection type. Choose **Next**. Review all settings on the summary page and choose **Submit** to create the collection.

After you submit, the collection enters a **Creating** status. When the status changes to **Active**, the collection is ready to use.

**Topics**
+ [Configure automatic semantic enrichment](#serverless-create-console-step-3-semantic-enrichment-fields)
+ [Configure time series search fields](#serverless-create-console-step-3-time-series-fields)
+ [Configure lexical search fields](#serverless-create-console-step-3-lexical-fields)
+ [Configure vector search fields](#serverless-create-console-step-3-vector-search-fields)

#### Configure automatic semantic enrichment
<a name="serverless-create-console-step-3-semantic-enrichment-fields"></a>

When you create or edit a collection, you can configure automatic semantic enrichment, which simplifies semantic search implementation and capabilities in Amazon OpenSearch Service. Semantic search returns query results that incorporate not just keyword matching, but the intent and contextual meaning of the user's search. For more information, see [Automatic semantic enrichment for Serverless](serverless-semantic-enrichment.md).

**To configure automatic semantic enrichment**

1. In the **Index details** section, for **Index name**, specify a name.

1. In the **Automatic semantic enrichment fields** section, choose **Add semantic search field**.

1. In the **Input field name for semantic enrichment** field, enter the name of a field that you want to enrich.

1. **Data type** is **Text**. You can't change this.

1. For **Language**, choose either **English** or **Multilingual**.

1. Choose **Add field**.

1. After you finish configuring optional fields for your collection, choose **Next**.

1. Review your changes and choose **Submit** to create the collection.

#### Configure time series search fields
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The options in the **Time series search fields** section pertain to time series data and data streams. For more information about these subjects, see [Managing time-series data in Amazon OpenSearch Service with data streams](data-streams.md).

**To configure time series search fields**

1. In the **Time series search fields** section, choose **Add time series field**.

1. For **Field name**, enter a name.

1. For **Data type**, choose a type from the list.

1. Choose **Add field**.

1. After you finish configuring optional fields for your collection, choose **Next**.

1. Review your changes and choose **Submit** to create the collection.

#### Configure lexical search fields
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Lexical search seeks an exact match between a search query and indexed terms or keywords.

**To configure lexical search fields**

1. In the **Lexical search fields** section, choose **Add search field**.

1. For **Field name**, enter a name.

1. For **Data type**, choose a type from the list.

1. Choose **Add field**.

1. After you finish configuring optional fields for your collection, choose **Next**.

1. Review your changes and choose **Submit** to create the collection.

#### Configure vector search fields
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**Note**  
The `Engine` property is only configurable with Classic collections and is unsupported for NextGen collections.

**To configure vector search fields**

1. In the **Vector fields** section, choose **Add vector field**.

1. For **Field name**, enter a name.

1. For **Engine**, choose a type from the list.

1. Enter the number of dimensions.

1. For **Distance Metric**, choose a type from the list.

1. After you finish configuring optional fields for your collection, choose **Next**.

1. Review your changes and choose **Submit** to create the collection.