# Configure an External Catalog
This page outlines how to connect an external catalog on the Immuta app settings page. For details on external catalogs with Immuta, see the [External catalog reference page](https://documentation.immuta.com/2024.3/integrations/catalogs/reference-guides/pre-configuration).
## Link an Alation catalog
**Requirements**:
* `APPLICATION_ADMIN` Immuta permission
* An [Alation API access token](https://developer.alation.com/dev/docs/authentication-into-alation-apis#create-an-api-access-token) connected to a user with the [`Server Admin`](https://developer.alation.com/dev/docs/alation-apis-by-roles) permission
{% hint style="info" %}
To change the default expiration period for your Alation catalog's API tokens, see [configure the expiration period for Alation API tokens](https://docs2.alationdata.com/en/latest/admins/AdditionalConfiguration/ConfigureAPITokensManagement.html#configure-the-expiration-period-for-api-tokens).
{% endhint %}
1. Navigate to the **App Settings** page.
2. Scroll to **2 External Catalogs**, and click **Add Catalog**.
3. Enter a **Display Name** and select **Alation** from the dropdown menu.
4. Complete the **URL** and **API key** fields. The API key must be an API access token for your Alation instance connected to a user with the [`Server Admin`](https://developer.alation.com/dev/docs/alation-apis-by-roles) permission.
5. Configure whether or not Alation tags and custom fields are imported as Immuta tags:
* **Link Alation tags**: When selected, Immuta imports Alation tags as Immuta tags.
* **Link Alation Custom Fields**: When selected, Immuta imports Alation custom fields as Immuta tags. Follow the Alation documentation to [create an Alation custom field](https://docs.alation.com/en/latest/steward/TemplatesAndCustomFields/ManageCustomFields.html#create-or-edit-a-custom-field), [add permissions to your custom field](https://docs.alation.com/en/latest/steward/TemplatesAndCustomFields/ManageCustomFields.html#add-permissions-to-a-custom-field), and apply custom fields to tables and columns.
6. Opt to select **Upload Certificates**.
1. Upload the **Certificate Authority**, **Certificate File**, and **Key File**.
2. Opt to enable **Strict SSL** by selecting the checkbox.
7. Click the **Test Connection** button.
8. Once the connection is successful, click **Save**.
## Link a Collibra catalog
**Requirement**: `APPLICATION_ADMIN` Immuta permission
1. Navigate to the **App Settings** page.
2. Scroll to **2 External Catalogs**, and click **Add Catalog**.
3. Enter the **Display Name** and select **Collibra** from the dropdown menu.
4. Enter the HTTP endpoint of the catalog in the **URL** field.
5. Complete the **Username** and **Password** fields. *Note: This is the username and the password that Immuta can use to connect to the external catalog.*
6. Opt to **Require the data source name in Collibra to contain both the schema and table name** by selecting the checkbox.
7. Complete the **Asset Mappings** modal to set which asset types in Collibra should align to Immuta's data sources and columns.
8. Complete the **Attributes as Tags** modal to specify which Collibra attributes you would like to pull in as tags in Immuta.
9. Opt to select **Upload Certificates**.
1. Upload the **Certificate Authority**, **Certificate File**, and **Key File**.
2. Opt to enable **Strict SSL** by selecting the checkbox.
10. Click the **Test Connection** button.
11. Once the connection is successful, click **Save**.
## Link a Microsoft Purview external catalog
{% hint style="info" %}
**Private preview**
The Microsoft Purview catalog integration is only available to select accounts. Contact your Immuta representative to enable this feature.
{% endhint %}
**Requirement**: `APPLICATION_ADMIN` Immuta permission
#### **Prerequisite**
[Register an app in the Azure portal](https://learn.microsoft.com/en-us/entra/identity-platform/quickstart-register-app) with the with the following settings:
* Supported account type: "Accounts in this organizational directory only"
* `Microsoft-Graph: User.Read` API permission
* A client secret
Using that registered app, navigate to Immuta and complete the following:
1. Navigate to the **App Settings** page.
2. Scroll to **2 External Catalogs**, and click **Add Catalog**.
3. Enter the **Display Name** and select **Microsoft Purview** from the dropdown menu.
4. Complete the following fields:
1. Enter the Microsoft Purview endpoint URL including the Azure Account Name, like `https://.purview.azure.com`, in the **Purview Endpoint URL** field.
2. Complete the **Microsoft Entra Directory (tenant) ID** and **Microsoft Entra (client) ID** fields.
3. Enter the **Microsoft Entra Application Client Secret ID** for Immuta to authenticate and connect to the Purview API. The secret cannot be expired.
5. Click the **Test Connection** button.
6. Once the test is successful, click **Save**.
## Link a custom REST catalog
**Requirement**: `APPLICATION_ADMIN` Immuta permission
Integrating a custom REST catalog service with Immuta requires implementing a REST interface. For details about the necessary endpoints that must be serviced, see the [Custom REST catalog interface endpoints page](https://documentation.immuta.com/2024.3/integrations/catalogs/reference-guides/custom-rest-catalogs/interface).
1. Navigate to the **App Settings** page.
2. Scroll to **2 External Catalogs**, and click **Add Catalog**.
3. Enter the **Display Name** and select **Rest** from the dropdown menu.
4. Select the **Internal Plugin** checkbox if the catalog has been uploaded to Immuta as a custom server plugin.
5. Complete the following fields:
1. Enter the HTTP endpoint of the catalog in the **URL** field.
2. Complete the **Username** and **Password** fields.
3. Enter the path of the **Tags Endpoint**.
4. Enter the path of the **Data Source Endpoint**.
5. Enter the path to the information page for a data source in the **Data Source Link Template** field.
6. Opt to enter the path to the information page for a column in the **Column Link Template** field.
7. Opt to upload a **Catalog Image**.
8. Opt to select **Upload Certificates**.
1. Upload the **Certificate Authority**, **Certificate File**, and **Key File**.
2. Opt to enable **Strict SSL** by selecting the checkbox.
9. Click the **Test Connection** button.
10. Click the **Test Data Source Link**.
11. Once both tests are successful, click **Save**.
## Enable Snowflake tag ingestion
See the [Configure a Snowflake integration](https://documentation.immuta.com/2024.3/snowflake/how-to-guides/enterprise#opt-to-enable-snowflake-tag-ingestion) page for guidance on configuring tag ingestion.
If Snowflake data sources existed before configuring tag ingestion, Immuta will automatically sync those data sources to the catalog and apply tags to them. Immuta will automatically check the external catalog for changes and sync data sources to the catalog every 24 hours.
## Enable Databricks Unity Catalog tag ingestion
See the [Configure a Databricks Unity Catalog integration](https://documentation.immuta.com/2024.3/databricks-unity-catalog/how-to-guides/configure#opt-to-enable-databricks-unity-catalog-tag-ingestion) page for guidance on configuring tag ingestion.
If Databricks Unity Catalog data sources existed before configuring tag ingestion, Immuta will automatically sync those data sources to the catalog and apply tags to them. Immuta will automatically check the external catalog for changes and sync data sources to the catalog every 24 hours.
## Manually link catalogs to data sources
You can manually link and remove external catalogs from data sources on the data source details tab.
1. Navigate to your data source.
2. In the connection information section, click the **Link Catalog** icon (or **Unlink Catalog** to remove an external catalog from a data source).
3. Select your **external catalog** from the dropdown menu.
4. Click **Link** to confirm.
## Manually sync external catalog tags
1. Navigate to your data source and click the data source **Health** dropdown menu.
2. Click **Re-run** in the External Catalog section.