<a id="cc-datastax-sink"></a>

# DataStax Sink Connector for Confluent Cloud

The fully managed DataStax Sink connector for Confluent Cloud streams records from
Apache Kafka® topics into Apache Cassandra, DataStax Enterprise (DSE), or
DataStax Astra DB tables, without managing any connector infrastructure.

If you require private networking for fully managed connectors, make sure to set up the proper
networking beforehand. For more information, see [Manage Networking for Confluent Cloud Connectors](networking/internet-resource.md#clusters-connect-cloud).

## Features

The DataStax Sink connector offers the following features:

* **Multiple targets**: Writes to Apache Cassandra 2.1 and later, DSE 4.7
  and later, or DataStax Astra DB, using the same connector configuration.
* **Multiple input formats**: Supports AVRO, JSON_SR (JSON Schema),
  PROTOBUF, JSON (schemaless), or BYTES input data formats.
  [Schema Registry](../get-started/schema-registry.md#cloud-sr-config) must be enabled to use a
  Schema Registry-based format such as AVRO, JSON_SR, or PROTOBUF.
* **Declarative topic-to-table mapping**: Maps record fields to table
  columns using the connector’s mapping domain-specific language (DSL),
  including fan-out from a single topic to multiple tables and consuming
  from multiple topics in one connector.
* **Row-level TTL and writetime overrides**: Sets a row’s time-to-live
  (TTL) and write timestamp from values in the Kafka record, so data ages
  out and orders correctly without a separate cleanup job.
* **Flexible security and networking**: Connects using TLS, PLAIN, or
  mutual TLS (mTLS) authentication, and supports private networking options where available
  on your cluster.

For more information and examples to use with the Confluent Cloud API for Connect,
see the [Confluent Cloud API for Connect Usage Examples](connect-api-section.md#ccloud-connect-api) section.

## Limitations

* For connector limitations, see [DataStax Sink Connector](limits.md#cc-datastax-sink-limits).
* If you plan to use one or more Single Message Transformations (SMTs), see
  [SMT Limitations](single-message-transforms.md#cc-single-message-transforms-limitations).

- If you plan to use one or more Custom SMTs, see [Custom SMT limitations](configure-custom-single-message-transforms/custom-smt-limitations-support.md#cc-custom-smt-limitations).

## Quick start

Select the connector and configure it to stream Kafka events into Cassandra,
DSE, or Astra DB tables.

<a id="cc-datastax-sink-prereqs"></a>

### Prerequisites

- Authorized access to a [Confluent Cloud](https://www.confluent.io/confluent-cloud/) cluster on Amazon Web Services (AWS), Microsoft Azure (Azure), or Google Cloud.
- The Confluent CLI installed and configured for the cluster. For more information,
  see [Install the Confluent CLI](https://docs.confluent.io/confluent-cli/current/install.html).
- [Schema Registry](../get-started/schema-registry.md#cloud-sr-config) must be enabled to use a Schema Registry-based
  format, such as AVRO, JSON_SR (JSON Schema), or PROTOBUF. For more
  information, see [Limits for Fully Managed Connectors for Confluent Cloud](limits.md#connect-ccloud-limits).
- Access to an Apache Cassandra, DSE, or DataStax Astra DB target, with the
  destination keyspace, tables, and any user-defined types (UDTs) or frozen
  collections already created. The connector does not create these automatically.
- Database credentials with write access to the target keyspace. For Astra DB,
  a Secure Connect Bundle (SCB) downloaded from the Astra console.
- For networking considerations, see [Networking and DNS](overview.md#connect-internet-access-resources).
  To use a set of public egress IP addresses, see [Public Egress IP Addresses for Confluent Cloud Connectors](static-egress-ip.md#cc-static-egress-ips).

- Kafka cluster credentials. The following lists the different ways you can provide credentials.
  - Enter an existing [service account](service-account.md#s3-cloud-service-account) resource ID.
  - Create a Confluent Cloud [service account](service-account.md#s3-cloud-service-account) for the connector. Make sure to review the ACL entries required in the [service account documentation](service-account.md#s3-cloud-service-account). Some connectors have specific ACL requirements.
  - Create a Confluent Cloud API key and secret. To create a key and secret, you can use [confluent api-key create](https://docs.confluent.io/confluent-cli/current/command-reference/api-key/confluent_api-key_create.html) *or* you can autogenerate the API key and secret directly in the Cloud Console when setting up the connector.

### Using the Confluent Cloud Console

#### Step 1: Launch your Confluent Cloud cluster

To create and launch a Kafka cluster in Confluent Cloud, see [Create a kafka cluster in Confluent Cloud](../get-started/index.md#cloud-create-kafka-cluster).

#### Step 2: Add a connector

In the left navigation menu, click **Connectors**. If you already have connectors in your cluster, click **+ Add
connector**.

#### Step 3: Select your connector

Click the **DataStax Sink** connector card.

![DataStax Sink Connector Card](images/ccloud-datastax-sink-icon.png)

<a id="cc-datastax-sink-setup-connection"></a>

#### Step 4: Enter the connector details

Before configuring the connector settings,
ensure that you complete all [prerequisites](#cc-datastax-sink-prereqs).

#### NOTE
An asterisk ( \* ) designates a required entry.

At the **Add DataStax Sink Connector** screen, complete the following:

### Topic selection

If you’ve already populated your Kafka topics, select the topics you want
to connect from the **Topics** list.

To create a new topic, click **+Add new topic**.

### Kafka access

1. Select the way you want to provide **Kafka Cluster credentials**. You can
   choose one of the following options:
   - **My account**: This setting allows your connector to globally access everything
     that you have access to. With a user account, the connector uses an API key and
     secret to access the Kafka cluster. This option is not recommended for production.
   - **Service account**: This setting limits the access for your connector by using a
     [service account](service-account.md#s3-cloud-service-account). This option is recommended for
     production.
   - **Use an existing API key**: This setting allows you to specify an API key and a
     secret pair. You can use an existing pair or create a new one. This method is not
     recommended for production environments.

   #### NOTE
   Freight clusters support only service accounts for Kafka authentication.
2. Click **Continue**.

### Authentication

1. Choose the **Deployment type**, either `Apache Cassandra or DSE`
   or `DataStax Astra`, and configure the matching connection and
   authentication properties:

   **How should we connect to Cassandra / DSE / Astra?**
   - **Deployment type**: The database you are connecting to. Choose `Apache Cassandra or DSE` to connect through contact points (optionally with SSL/TLS), or `DataStax Astra` to connect through an uploaded Secure Connect Bundle. The two modes are mutually exclusive and the connector cannot use both at once. For CLI or Terraform provisioning, set this explicitly.
   - **Cassandra/DSE contact points**: Comma-separated host names or IPs of the Cassandra or DSE cluster contact points. Used only for the `Apache Cassandra or DSE` deployment type. Leave this empty for Astra and use the Secure Connect Bundle instead.
   - **Native transport port**: Cassandra/DSE native transport port (ignored for Astra).
   - **Local datacenter**: Name of the local datacenter the driver should treat as local (commonly `dc1`). Required for the `Apache Cassandra or DSE` deployment type. Must not be set for Astra.
   - **Astra Secure Connect Bundle**: DataStax Astra DB Secure Connect Bundle (SCB). Required for the `DataStax Astra` deployment type, and mutually exclusive with contact points, local datacenter, or SSL settings. Upload the SCB zip file. For REST API usage base64-encode it and prefix with `data:application/octet-stream;base64,`.

   **Authentication**
   - **Authentication provider**: Authentication provider to the database. `None` for no authentication, `PLAIN` for username/password (also used for LDAP and for Astra token authentication).
   - **Username**: Database username for `PLAIN` authentication. For Astra token authentication use the literal `token`.
   - **Password**: Database password for `PLAIN` authentication. For Astra token authentication use the `AstraCS:...` token.

   **Security (SSL/TLS)**
   - **SSL/TLS provider**: SSL/TLS engine used for the connection to Cassandra/DSE. `None` disables SSL. `JDK` uses the JSSE keystore/truststore (JKS). `OpenSSL` uses PEM certificate and private key files. Only applicable to the `Apache Cassandra or DSE` deployment type — Astra’s TLS material is carried inside the Secure Connect Bundle.
   - **Validate server hostname**: Whether to validate the database node hostnames against the certificate when SSL is enabled.
   - **Truststore file**: Truststore file (JKS) containing the CA certificate(s) that sign the database server certificates. Upload the file. For REST API usage base64-encode it and prefix with `data:application/octet-stream;base64,`.
   - **Truststore password**: Password protecting the truststore file. Leave empty if the truststore has no password.
   - **Keystore file (mTLS)**: Keystore file (JKS) holding the client certificate and private key for mutual TLS (client authentication). Only needed when the database requires client certificates. Upload the file. For REST API usage base64-encode it and prefix with `data:application/octet-stream;base64,`.
   - **Keystore password**: Password protecting the keystore file (leave empty if the keystore has no password).
   - **Cipher suites**: Optional comma-separated list of TLS cipher suites to enable. Leave empty to use the JVM defaults.
2. Click **Continue**.

### Configuration

#### NOTE
Configuration properties that are not shown in the
Cloud Console use the default values. For all property
values and definitions, see [Configuration Properties](#cc-datastax-sink-config-properties).

- **Input Kafka record value format**: Sets the input Kafka record value format. Valid entries are AVRO, JSON_SR, PROTOBUF, JSON, or BYTES. Note that you need to have Confluent Cloud Schema Registry configured if using a schema-based message format like AVRO, JSON_SR, and PROTOBUF.

**Table mapping**

- **Topic-to-table field mapping**: JSON object mapping each `<topic>.<keyspace>.<table>` to its field-to-column mapping, for example `{"orders.ecom.orders":"id=value.id, amount=value.amount"}`. Use `key.*` to reference record-key fields (primary-key columns) and `value.*` for record-value fields. Each entry materializes to the engine key `topic.<topic>.<keyspace>.<table>.mapping`. A single topic can map to multiple tables (fan-out) by adding multiple entries.

**Data decryption**

- Enable **Client-Side Field Level Encryption** for
  data decryption. Specify a **Service Account** to
  access the Schema Registry and associated encryption rules or keys with that schema. Select the connector behavior
  (`ERROR` or `NONE`) on data decryption failure. If set to `ERROR`, the connector fails and writes the encrypted data
  in the DLQ. If set to `NONE`, the connector writes the encrypted data in the target system without decryption.
  For more information on CSFLE or CSPE setup, see [Manage encryption for connectors](csfle.md#connect-csfle).

### **Show advanced configurations**

- **Schema context**: Select a schema context to use for this connector, if using
  a schema-based data format. This property defaults to the **Default** context,
  which configures the connector to use the default schema set up for Schema Registry in your
  Confluent Cloud environment. A schema context allows you to use separate schemas (like
  schema sub-registries) tied to topics in different Kafka clusters that share the
  same Schema Registry environment. For example, if you select a non-default context, a
  **Source** connector uses only that schema context to register a schema and a
  **Sink** connector uses only that schema context to read from. For more
  information about setting up a schema context, see [What are schema contexts and when should you use them?](../sr/faqs-cc.md#faq-schema-contexts).
- **Input Kafka record key format**: Sets the input Kafka record key format. Valid entries are AVRO, BYTES, JSON, JSON_SR, PROTOBUF, or STRING. Note that you need to have Confluent Cloud Schema Registry configured if using a schema-based message format like AVRO, JSON_SR, and PROTOBUF.

**Additional Configs**

- **Value Converter Replace Null With Default**: Specifies whether to replace fields that have a default value and that are null to the default value. When set to `true`, the connector uses the default value; otherwise, it uses `null`. Applies to the `JSON` converter.
- **Value Converter Schema ID Deserializer**: Sets the class name of the schema ID deserializer for values. The deserializer reads schema IDs from message headers.
- **Value Converter Reference Subject Name Strategy**: Sets the subject reference name strategy for values. Valid entries are `DefaultReferenceSubjectNameStrategy` or `QualifiedReferenceSubjectNameStrategy`. You can use this strategy only with `PROTOBUF` format; the default strategy is `DefaultReferenceSubjectNameStrategy`.
- **Schema ID For Value Converter**: Sets the schema ID to use for deserialization when using `ConfigSchemaIdDeserializer`. This lets you specify a fixed schema ID for deserializing message values. This property is applicable only when `value.converter.value.schema.id.deserializer` is set to `ConfigSchemaIdDeserializer`.
- **Value Converter Schemas Enable**: Includes schema within each of the serialized values. Input messages must contain `schema` and `payload` fields and must not contain additional fields. For plain `JSON` data, set this to `false`. Applies to the `JSON` converter.
- **Errors Tolerance**: Use this property to configure the connector’s error handling behavior.

  #### WARNING
  Use this property with caution for sink connectors, as it can lead to data loss. If you set this property to `all`, the connector does not fail on errant records, but logs them (and sends to DLQ for sink connectors) and continues processing. If you set this property to `none`, the connector task fails on errant records.
- **Value Converter Ignore Default For Nullables**: When set to `true`, this property ensures that the corresponding record in Kafka is `null`, instead of showing the default column value. Applies to the `AVRO`, `PROTOBUF`, and `JSON_SR` converters.
- **Key Converter Schema ID Deserializer**: Sets the class name of the schema ID deserializer for keys. The deserializer reads schema IDs from message headers.
- **Value Converter Decimal Format**: Specifies the `JSON` or `JSON_SR` serialization format for Connect `DECIMAL` logical type values with two allowed literals:
  `BASE64` to serialize `DECIMAL` logical types as base64 encoded binary data, and
  `NUMERIC` to serialize `DECIMAL` logical type values in `JSON` or `JSON_SR` as a number representing the decimal value.
- **Schema GUID For Key Converter**: Sets the schema GUID to use for deserialization when using `ConfigSchemaIdDeserializer`. This lets you specify a fixed schema GUID for deserializing message keys. This property is applicable only when `key.converter.key.schema.id.deserializer` is set to `ConfigSchemaIdDeserializer`.
- **Schema GUID For Value Converter**: Sets the schema GUID to use for deserialization when using `ConfigSchemaIdDeserializer`. This lets you specify a fixed schema GUID for deserializing message values. This property is applicable only when `value.converter.value.schema.id.deserializer` is set to `ConfigSchemaIdDeserializer`.
- **Value Converter Connect Meta Data**: Enables the Connect converter to add its metadata to the output schema. Applies to Avro converters.
- **Value Converter Value Subject Name Strategy**: Determines how to construct the subject name under which the value schema is registered with Schema Registry.
- **Key Converter Key Subject Name Strategy**: Determines how to construct the subject name for key schema registration.
- **Schema ID For Key Converter**: Sets the schema ID to use for deserialization when using `ConfigSchemaIdDeserializer`. This lets you specify a fixed schema ID for deserializing message keys. This property is applicable only when `key.converter.key.schema.id.deserializer` is set to `ConfigSchemaIdDeserializer`.

**Auto-restart policy**

- **Enable Connector Auto-restart**: Enables the auto-restart behavior of the connector and its
  task in the event of user-actionable errors. Defaults to `true`, enabling the connector to
  automatically restart in case of user-actionable errors. Set this property to `false` to
  disable auto-restart for failed connectors. If disabled, you must manually restart the connector.

**Consumer configuration**

- **Max poll interval(ms)**: Sets the maximum delay between subsequent consume requests to Kafka. Use this property to
  improve connector performance in cases when the connector cannot send records to the sink system.
  The default is 300,000 milliseconds (5 minutes).
- **Max poll records**: Sets the maximum number of records to consume from Kafka in a single request. Use this property to
  improve connector performance in cases when the connector cannot send records to the sink system.
  The default is 500 records.

**Table mapping**

- **Per-table / per-topic overrides**: Optional JSON object of per-table and per-topic overrides. Per-table keys
  are `<topic>.<keyspace>.<table>.<setting>` where `<setting>` is one
  of `consistencyLevel`, `ttl`, `ttlTimeUnit`, `timestampTimeUnit`,
  `nullToUnset`, `deletesEnabled`, or `query`. Per-topic codec keys
  are `<topic>.codec.<setting>` where `<setting>` is one of `locale`,
  `timeZone`, `timestamp`, `date`, `time`, or `unit`.
  Example: `{"orders.ecom.orders.consistencyLevel":"LOCAL_QUORUM",
  "orders.ecom.orders.ttl":"3600", "orders.codec.timeZone":"UTC"}`.
  Each entry materializes to the engine key `topic.<entry-key>`.

**Connection tuning**

- **Max concurrent requests**: Maximum number of requests to send to the database at once.
- **Max records per batch**: Maximum number of records sent in a single UNLOGGED batch request.
- **Query execution timeout (s)**: CQL statement execution timeout, in seconds.
- **Local connection pool size**: Number of connections the driver maintains to each node in the local datacenter.
- **Protocol compression**: Compression algorithm to use for requests to the database server.

**Transforms**

- **Single Message Transformations**: To add a new SMT, see [Add transforms](single-message-transforms.md#cc-single-message-transforms-ui).
  For more information about unsupported SMTs, see
  [Unsupported transformations](single-message-transforms.md#cc-single-message-transforms-unsupported-transforms).

For all property values and definitions, see [Configuration Properties](#cc-datastax-sink-config-properties).

- Click **Continue**.

### Sizing

Based on the number of topic partitions you select, Confluent Cloud
recommends a number of tasks.

1. To change the number of recommended tasks, enter the number of
   [tasks](/platform/current/connect/concepts.html#tasks) for the connector to
   use in the **Tasks** field.
2. Click **Continue**.

### Review and Launch

1. Verify the connection details.
2. Click **Launch**.

   The status for the connector should go from **Provisioning** to
   **Running**.

#### Step 5: Check the target database

After the connector is running, verify that records are populating the
mapped tables in your Cassandra, DSE, or Astra DB keyspace.

For more information and examples to use with the Confluent Cloud API for Connect,
see the [Confluent Cloud API for Connect Usage Examples](connect-api-section.md#ccloud-connect-api) section.

### Using the Confluent CLI

Complete the following steps to set up and run the connector using the
Confluent CLI.

#### NOTE
Make sure you have all your [prerequisites](#cc-datastax-sink-prereqs) completed.

#### Step 1: List the available connectors

Enter the following command to list available connectors:

```none
confluent connect plugin list
```

#### Step 2: List the connector configuration properties

Enter the following command to show the connector configuration properties:

```none
confluent connect plugin describe <connector-plugin-name>
```

The command output shows the required and optional configuration properties.

#### Step 3: Create the connector configuration file

Create a JSON file that contains the connector configuration properties.
The following example shows the required properties for connecting to
Apache Cassandra or DSE.

```json
{
  "connector.class": "DataStaxSink",
  "name": "DataStaxSinkConnector_0",
  "topics": "orders",
  "kafka.auth.mode": "KAFKA_API_KEY",
  "kafka.api.key": "<my-kafka-api-key>",
  "kafka.api.secret": "<my-kafka-api-secret>",
  "input.data.format": "AVRO",
  "deployment.type": "Apache Cassandra or DSE",
  "contactPoints": "<cassandra-host-1>,<cassandra-host-2>",
  "port": "9042",
  "loadBalancing.localDc": "<local-datacenter-name>",
  "auth.provider": "PLAIN",
  "auth.username": "<database-username>",
  "auth.password": "<database-password>",
  "mapping.map": "{\"orders.ecom.orders\":\"id=value.id, amount=value.amount\"}",
  "tasks.max": "1"
}
```

To connect to DataStax Astra DB instead, remove the `contactPoints`,
`port`, and `loadBalancing.localDc` properties and add the following properties:

```json
{
  "deployment.type": "DataStax Astra",
  "cloud.secureConnectBundle": "<base64-encoded-secure-connect-bundle>",
  "auth.provider": "PLAIN",
  "auth.username": "token",
  "auth.password": "<astra-application-token>"
}
```

Note the following property definitions:

* `"connector.class"`: Identifies the connector plugin name.
* `"name"`: Sets a name for your new connector.
* `"topics"`: Identifies the topic name or a comma-separated list of
  topic names.
* `"input.data.format"`: Sets the input Kafka record value format. Valid
  entries are AVRO, JSON_SR, PROTOBUF, JSON, or BYTES. You must have
  Confluent Cloud Schema Registry configured if using a schema-based message format such as
  AVRO, JSON_SR, or PROTOBUF.

* `"kafka.auth.mode"`: Identifies the connector authentication mode you want to use. There are two options: `SERVICE_ACCOUNT` or `KAFKA_API_KEY` (the default). To use an API key and secret, specify the configuration properties `kafka.api.key` and `kafka.api.secret`, as shown in the example configuration (above).  To use a [service account](service-account.md#s3-cloud-service-account), specify the **Resource ID** in the property `kafka.service.account.id=<service-account-resource-ID>`. To list the available service account resource IDs, use the following command:
  ```bash
  confluent iam service-account list
  ```

  For example:
  ```bash
  confluent iam service-account list

     Id     | Resource ID |       Name        |    Description
  +---------+-------------+-------------------+-------------------
     123456 | sa-l1r23m   | sa-1              | Service account 1
     789101 | sa-l4d56p   | sa-2              | Service account 2
  ```

* `"deployment.type"`: Sets which database you are connecting to. Use
  `Apache Cassandra or DSE` to connect using contact points, or
  `DataStax Astra` to connect using an uploaded SCB.
* `"contactPoints"`: Comma-separated host names or IP addresses of the
  Cassandra or DSE cluster contact points. Applies only when
  `deployment.type` is set to `Apache Cassandra or DSE`.
* `"loadBalancing.localDc"`: The name of the local datacenter the driver
  treats as local, for example `dc1`. Required when `deployment.type`
  is set to `Apache Cassandra or DSE`.
* `"cloud.secureConnectBundle"`: The base64-encoded Astra DB SCB. Required when `deployment.type` is set to
  `DataStax Astra`.
* `"mapping.map"`: A JSON object that maps each
  `<topic>.<keyspace>.<table>` to its field-to-column mapping. A single
  topic can map to multiple tables by adding multiple entries. For all
  mapping syntax and per-table override properties, see
  [Configuration Properties](#cc-datastax-sink-config-properties).

#### NOTE
To enable CSFLE or CSPE for data encryption, specify the following properties:

* `csfle.enabled`: Flag to indicate whether the connector honors CSFLE or CSPE rules.
* `sr.service.account.id`: A Service Account to access the Schema Registry and associated encryption rules or keys with that schema.
* `csfle.onFailure`: Configures the connector behavior (`ERROR` or `NONE`) on data decryption failure.
  If set to `ERROR`, the connector fails and writes the encrypted data
  in the DLQ. If set to `NONE`, the connector writes the encrypted data in the target system without decryption.

When using CSFLE or CSPE with connectors that route failed messages to a Dead Letter Queue (DLQ),
be aware that data sent to the DLQ is written in unencrypted plaintext. This poses
a significant security risk as sensitive data that should be encrypted may be exposed in the DLQ.

Do not use DLQ with CSFLE or CSPE in the current version. If you need error handling for
CSFLE- or CSPE-enabled data, use alternative approaches such as:

* Setting the connector behavior to `ERROR` to throw exceptions instead of routing to DLQ
* Implementing custom error handling in your applications
* Using `NONE` to pass encrypted data through without decryption

For more information on CSFLE or CSPE setup, see [Manage encryption for connectors](csfle.md#connect-csfle).

**SMTs**: For details about adding SMTs using the Confluent CLI, see the
[Single Message Transformations](single-message-transforms.md#cc-single-message-transforms)
documentation.

For all configuration property values and descriptions, see
[Configuration Properties](#cc-datastax-sink-config-properties).

#### Step 4: Load the configuration file and create the connector

Enter the following command to load the configuration and start the
connector:

```none
confluent connect cluster create --config-file <file-name>.json
```

For example:

```none
confluent connect cluster create --config-file datastax-sink-config.json
```

Example output:

```none
Created connector DataStaxSinkConnector_0 lcc-ix4dl
```

#### Step 5: Check the connector status

Enter the following command to check the connector status:

```none
confluent connect cluster list
```

Example output:

```none
ID          |          Name              | Status  | Type
+-----------+----------------------------+---------+------+
lcc-ix4dl   | DataStaxSinkConnector_0    | RUNNING | sink
```

#### Step 6: Check the target database

After the connector is running, verify that records are populating the
mapped tables in your Cassandra, DSE, or Astra DB keyspace.

For more information and examples to use with the Confluent Cloud API for Connect,
see the [Confluent Cloud API for Connect Usage Examples](connect-api-section.md#ccloud-connect-api) section.

<a id="cc-datastax-sink-config-properties"></a>

## Configuration Properties

Use the following configuration properties with the fully managed
connector.

### How should we connect to your data?

`name`
: Sets a name for your connector.
  <br/>
  * Type: string
  * Valid Values: A string at most 64 characters long
  * Importance: high

### Schema Config

`schema.context.name`
: Add a schema context name. A schema context represents an independent scope in Schema Registry. It is a separate sub-schema tied to topics in different Kafka clusters that share the same Schema Registry instance. If not used, the connector uses the default schema configured for Schema Registry in your Confluent Cloud environment.
  <br/>
  * Type: string
  * Default: default
  * Importance: medium

### Input messages

`input.data.format`
: Sets the input Kafka record value format. Valid entries are AVRO, JSON_SR, PROTOBUF, JSON or BYTES. Note that you need to have Confluent Cloud Schema Registry configured if using a schema-based message format like AVRO, JSON_SR, and PROTOBUF.
  <br/>
  * Type: string
  * Default: JSON
  * Importance: high

`input.key.format`
: Sets the input Kafka record key format. Valid entries are AVRO, BYTES, JSON, JSON_SR, PROTOBUF, or STRING. Note that you need to have Confluent Cloud Schema Registry configured if using a schema-based message format like AVRO, JSON_SR, and PROTOBUF
  <br/>
  * Type: string
  * Default: JSON
  * Valid Values: AVRO, BYTES, JSON, JSON_SR, PROTOBUF, STRING
  * Importance: high

### Kafka Cluster credentials

`kafka.auth.mode`
: Kafka Authentication mode. It can be one of KAFKA_API_KEY or SERVICE_ACCOUNT. It defaults to KAFKA_API_KEY mode, whenever possible.
  <br/>
  * Type: string
  * Valid Values: SERVICE_ACCOUNT, KAFKA_API_KEY
  * Importance: high

`kafka.api.key`
: Kafka API Key. Required when kafka.auth.mode==KAFKA_API_KEY.
  <br/>
  * Type: password
  * Importance: high

`kafka.service.account.id`
: The Service Account that will be used to generate the API keys to communicate with Kafka Cluster.
  <br/>
  * Type: string
  * Importance: high

`kafka.api.secret`
: Secret associated with Kafka API key. Required when kafka.auth.mode==KAFKA_API_KEY.
  <br/>
  * Type: password
  * Importance: high

### Which topics do you want to get data from?

`topics.regex`
: A regular expression that matches the names of the topics to consume from. This is useful when you want to consume from multiple topics that match a certain pattern without having to list them all individually.
  <br/>
  * Type: string
  * Importance: low

`topics`
: Identifies the topic name or a comma-separated list of topic names.
  <br/>
  * Type: list
  * Importance: high

`errors.deadletterqueue.topic.name`
: The name of the topic to be used as the dead letter queue (DLQ) for messages that result in an error when processed by this sink connector, or its transformations or converters. Defaults to ‘dlq-${connector}’ if not set. The DLQ topic will be created automatically if it does not exist. You can provide `${connector}` in the value to use it as a placeholder for the logical cluster ID.
  <br/>
  * Type: string
  * Default: dlq-${connector}
  * Importance: low

### How should we connect to Cassandra / DSE / Astra?

`deployment.type`
: Which database you are connecting to. Choose `Apache Cassandra or DSE` to connect via contact points (optionally with SSL/TLS), or `DataStax Astra` to connect via an uploaded Secure Connect Bundle. The two modes are mutually exclusive — the connector cannot use both at once. For CLI/Terraform provisioning, set this explicitly.
  <br/>
  * Type: string
  * Default: Apache Cassandra or DSE
  * Valid Values: Apache Cassandra or DSE, DataStax Astra
  * Importance: high

`contactPoints`
: Comma-separated host names or IPs of the Cassandra/DSE cluster contact points. Used only for the `Apache Cassandra or DSE` deployment type; leave empty for Astra (use the Secure Connect Bundle instead).
  <br/>
  * Type: string
  * Default: “”
  * Importance: high

`port`
: Cassandra/DSE native transport port (ignored for Astra).
  <br/>
  * Type: int
  * Default: 9042
  * Valid Values: [1,…]
  * Importance: low

`loadBalancing.localDc`
: Name of the local datacenter the driver should treat as local (commonly `dc1`). Required for the `Apache Cassandra or DSE` deployment type; must not be set for Astra.
  <br/>
  * Type: string
  * Default: “”
  * Importance: medium

`cloud.secureConnectBundle`
: DataStax Astra DB Secure Connect Bundle (SCB). Required for the `DataStax Astra` deployment type, and mutually exclusive with contact points / local datacenter / SSL settings. Upload the SCB zip file; for REST API usage base64-encode it and prefix with `data:application/octet-stream;base64,`.
  <br/>
  * Type: password
  * Importance: high

### Authentication

`auth.provider`
: Authentication provider to the database. `None` for no auth, `PLAIN` for username/password (also used for LDAP and for Astra token auth).
  <br/>
  * Type: string
  * Default: None
  * Valid Values: None, PLAIN
  * Importance: medium

`auth.username`
: Database username (for `PLAIN` auth; for Astra token auth use the literal `token`).
  <br/>
  * Type: string
  * Default: “”
  * Importance: medium

`auth.password`
: Database password (for `PLAIN` auth; for Astra token auth use the `AstraCS:...` token).
  <br/>
  * Type: password
  * Importance: medium

### Security (SSL/TLS)

`ssl.provider`
: SSL/TLS engine used for the connection to Cassandra/DSE. `None` disables SSL. `JDK` uses the JSSE keystore/truststore (JKS). Only applicable to the `Apache Cassandra or DSE` deployment type — Astra’s TLS material is carried inside the Secure Connect Bundle.
  <br/>
  * Type: string
  * Default: None
  * Valid Values: JDK, None
  * Importance: medium

`ssl.hostnameValidation`
: Whether to validate the database node hostnames against the certificate when SSL is enabled.
  <br/>
  * Type: boolean
  * Default: true
  * Importance: medium

`ssl.truststore.path`
: Truststore file (JKS) containing the CA certificate(s) that sign the database server certificates. Upload the file; for REST API usage base64-encode it and prefix with `data:application/octet-stream;base64,`.
  <br/>
  * Type: password
  * Importance: medium

`ssl.truststore.password`
: Password protecting the truststore file (leave empty if the truststore has no password).
  <br/>
  * Type: password
  * Importance: medium

`ssl.keystore.path`
: Keystore file (JKS) holding the client certificate + private key for mutual TLS (client authentication). Only needed when the database requires client certificates. Upload the file; for REST API usage base64-encode it and prefix with `data:application/octet-stream;base64,`.
  <br/>
  * Type: password
  * Importance: medium

`ssl.keystore.password`
: Password protecting the keystore file (leave empty if the keystore has no password).
  <br/>
  * Type: password
  * Importance: medium

`ssl.cipherSuites`
: Optional comma-separated list of TLS cipher suites to enable. Leave empty to use the JVM defaults.
  <br/>
  * Type: string
  * Default: “”
  * Importance: low

### Table mapping

`mapping.map`
: JSON object mapping each `<topic>.<keyspace>.<table>` to its field-to-column mapping, e.g. `{"orders.ecom.orders":"id=value.id, amount=value.amount"}`. Use `key.*` to reference record-key fields (primary-key columns) and `value.*` for record-value fields. Each entry materializes to the engine key `topic.<topic>.<keyspace>.<table>.mapping`. A single topic may map to multiple tables (fan-out) by adding multiple entries.
  <br/>
  * Type: string
  * Default: “”
  * Importance: high

`topic.override.map`
: Optional JSON object of per-table and per-topic overrides. Per-table keys are `<topic>.<keyspace>.<table>.<setting>` where `<setting>` is one of `consistencyLevel`, `ttl`, `ttlTimeUnit`, `timestampTimeUnit`, `nullToUnset`, `deletesEnabled` or `query`. Per-topic codec keys are `<topic>.codec.<setting>` where `<setting>` is one of `locale`, `timeZone`, `timestamp`, `date`, `time` or `unit`. Example: `{"orders.ecom.orders.consistencyLevel":"LOCAL_QUORUM", "orders.ecom.orders.ttl":"3600", "orders.codec.timeZone":"UTC"}`. Each entry materializes to the engine key `topic.<entry-key>`.
  <br/>
  * Type: string
  * Default: {}
  * Importance: medium

### Connection tuning

`maxConcurrentRequests`
: Maximum number of requests to send to the database at once.
  <br/>
  * Type: int
  * Default: 500
  * Valid Values: [1,…]
  * Importance: low

`maxNumberOfRecordsInBatch`
: Maximum number of records sent in a single UNLOGGED batch request.
  <br/>
  * Type: int
  * Default: 32
  * Valid Values: [1,…]
  * Importance: low

`queryExecutionTimeout`
: CQL statement execution timeout, in seconds.
  <br/>
  * Type: int
  * Default: 30
  * Valid Values: [1,…]
  * Importance: low

`connectionPoolLocalSize`
: Number of connections the driver maintains to each node in the local datacenter.
  <br/>
  * Type: int
  * Default: 4
  * Valid Values: [1,…]
  * Importance: low

`compression`
: Compression algorithm to use for requests to the database server.
  <br/>
  * Type: string
  * Default: None
  * Valid Values: LZ4, None, SNAPPY
  * Importance: low

### Consumer configuration

`max.poll.interval.ms`
: The maximum delay between subsequent consume requests to Kafka. This configuration property may be used to improve the performance of the connector, if the connector cannot send records to the sink system. Defaults to 300000 milliseconds (5 minutes).
  <br/>
  * Type: long
  * Default: 300000 (5 minutes)
  * Valid Values: [60000,…,1800000] for non-dedicated clusters and [60000,…] for dedicated clusters
  * Importance: low

`max.poll.records`
: The maximum number of records to consume from Kafka in a single request. This configuration property may be used to improve the performance of the connector, if the connector cannot send records to the sink system. Defaults to 500 records.
  <br/>
  * Type: long
  * Default: 500
  * Valid Values: [1,…,500] for non-dedicated clusters and [1,…] for dedicated clusters
  * Importance: low

### Number of tasks for this connector

`tasks.max`
: Maximum number of tasks for the connector.
  <br/>
  * Type: int
  * Valid Values: [1,…]
  * Importance: high

### Additional Configs

`consumer.override.auto.offset.reset`
: Defines the behavior of the consumer when there is no committed position (which occurs when the group is first initialized) or when an offset is out of range. You can choose either to reset the position to the “earliest” offset (the default) or the “latest” offset. You can also select “none” if you would rather set the initial offset yourself and you are willing to handle out of range errors manually. More details: [https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#auto-offset-reset](https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#auto-offset-reset)
  <br/>
  * Type: string
  * Importance: low

`consumer.override.isolation.level`
: Controls how to read messages written transactionally. If set to read_committed, consumer.poll() will only return transactional messages which have been committed. If set to read_uncommitted (the default), consumer.poll() will return all messages, even transactional messages which have been aborted. Non-transactional messages will be returned unconditionally in either mode.  More details: [https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#isolation-level](https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#isolation-level)
  <br/>
  * Type: string
  * Importance: low

`header.converter`
: The converter class for the headers. This is used to serialize and deserialize the headers of the messages.
  <br/>
  * Type: string
  * Importance: low

`key.converter.use.schema.guid`
: The schema GUID to use for deserialization when using ConfigSchemaIdDeserializer. This allows you to specify a fixed schema GUID to be used for deserializing message keys. Only applicable when key.converter.key.schema.id.deserializer is set to ConfigSchemaIdDeserializer.
  <br/>
  * Type: string
  * Importance: low

`key.converter.use.schema.id`
: The schema ID to use for deserialization when using ConfigSchemaIdDeserializer. This allows you to specify a fixed schema ID to be used for deserializing message keys. Only applicable when key.converter.key.schema.id.deserializer is set to ConfigSchemaIdDeserializer.
  <br/>
  * Type: int
  * Importance: low

`value.converter.allow.optional.map.keys`
: Allow optional string map key when converting from Connect Schema to Avro Schema. Applicable for Avro Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.auto.register.schemas`
: Specify if the Serializer should attempt to register the Schema.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.connect.meta.data`
: Allow the Connect converter to add its metadata to the output schema. Applicable for Avro Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.enhanced.avro.schema.support`
: Enable enhanced schema support to preserve package information and Enums. Applicable for Avro Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.enhanced.protobuf.schema.support`
: Enable enhanced schema support to preserve package information. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.flatten.unions`
: Whether to flatten unions (oneofs). Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.generate.index.for.unions`
: Whether to generate an index suffix for unions. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.generate.struct.for.nulls`
: Whether to generate a struct variable for null values. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.int.for.enums`
: Whether to represent enums as integers. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.latest.compatibility.strict`
: Verify latest subject version is backward compatible when use.latest.version is true.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.object.additional.properties`
: Whether to allow additional properties for object schemas. Applicable for JSON_SR Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.optional.for.nullables`
: Whether nullable fields should be specified with an optional label. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.optional.for.proto2`
: Whether proto2 optionals are supported. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.scrub.invalid.names`
: Whether to scrub invalid names by replacing invalid characters with valid characters. Applicable for Avro and Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.use.latest.version`
: Use latest version of schema in subject for serialization when auto.register.schemas is false.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.use.optional.for.nonrequired`
: Whether to set non-required properties to be optional. Applicable for JSON_SR Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.use.schema.guid`
: The schema GUID to use for deserialization when using ConfigSchemaIdDeserializer. This allows you to specify a fixed schema GUID to be used for deserializing message values. Only applicable when value.converter.value.schema.id.deserializer is set to ConfigSchemaIdDeserializer.
  <br/>
  * Type: string
  * Importance: low

`value.converter.use.schema.id`
: The schema ID to use for deserialization when using ConfigSchemaIdDeserializer. This allows you to specify a fixed schema ID to be used for deserializing message values. Only applicable when value.converter.value.schema.id.deserializer is set to ConfigSchemaIdDeserializer.
  <br/>
  * Type: int
  * Importance: low

`value.converter.wrapper.for.nullables`
: Whether nullable fields should use primitive wrapper messages. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`value.converter.wrapper.for.raw.primitives`
: Whether a wrapper message should be interpreted as a raw primitive at root level. Applicable for Protobuf Converters.
  <br/>
  * Type: boolean
  * Importance: low

`errors.tolerance`
: Use this property if you would like to configure the connector’s error handling behavior. WARNING: This property should be used with CAUTION for SOURCE CONNECTORS as it may lead to dataloss. If you set this property to ‘all’, the connector will not fail on errant records, but will instead log them (and send to DLQ for Sink Connectors) and continue processing. If you set this property to ‘none’, the connector task will fail on errant records.
  <br/>
  * Type: string
  * Default: all
  * Importance: low

`key.converter.key.schema.id.deserializer`
: The class name of the schema ID deserializer for keys. This is used to deserialize schema IDs from the message headers.
  <br/>
  * Type: string
  * Default: io.confluent.kafka.serializers.schema.id.DualSchemaIdDeserializer
  * Importance: low

`key.converter.key.subject.name.strategy`
: How to construct the subject name for key schema registration.
  <br/>
  * Type: string
  * Default: TopicNameStrategy
  * Importance: low

`key.converter.replace.null.with.default`
: Whether to replace fields that have a default value and that are null to the default value. When set to true, the default value is used, otherwise null is used. Applicable for JSON Key Converter.
  <br/>
  * Type: boolean
  * Default: true
  * Importance: low

`key.converter.schemas.enable`
: Include schemas within each of the serialized keys. Input message keys must contain schema and payload fields and may not contain additional fields. For plain JSON data, set this to false. Applicable for JSON Key Converter.
  <br/>
  * Type: boolean
  * Default: false
  * Importance: low

`value.converter.decimal.format`
: Specify the JSON/JSON_SR serialization format for Connect DECIMAL logical type values with two allowed literals:
  <br/>
  BASE64 to serialize DECIMAL logical types as base64 encoded binary data and
  <br/>
  NUMERIC to serialize Connect DECIMAL logical type values in JSON/JSON_SR as a number representing the decimal value.
  <br/>
  * Type: string
  * Default: BASE64
  * Importance: low

`value.converter.flatten.singleton.unions`
: Whether to flatten singleton unions. Applicable for Avro and JSON_SR Converters.
  <br/>
  * Type: boolean
  * Default: false
  * Importance: low

`value.converter.ignore.default.for.nullables`
: When set to true, this property ensures that the corresponding record in Kafka is NULL, instead of showing the default column value. Applicable for AVRO,PROTOBUF and JSON_SR Converters.
  <br/>
  * Type: boolean
  * Default: false
  * Importance: low

`value.converter.reference.subject.name.strategy`
: Set the subject reference name strategy for value. Valid entries are DefaultReferenceSubjectNameStrategy or QualifiedReferenceSubjectNameStrategy. Note that the subject reference name strategy can be selected only for PROTOBUF format with the default strategy being DefaultReferenceSubjectNameStrategy.
  <br/>
  * Type: string
  * Default: DefaultReferenceSubjectNameStrategy
  * Importance: low

`value.converter.replace.null.with.default`
: Whether to replace fields that have a default value and that are null to the default value. When set to true, the default value is used, otherwise null is used. Applicable for JSON Converter.
  <br/>
  * Type: boolean
  * Default: true
  * Importance: low

`value.converter.schemas.enable`
: Include schemas within each of the serialized values. Input messages must contain schema and payload fields and may not contain additional fields. For plain JSON data, set this to false. Applicable for JSON Converter.
  <br/>
  * Type: boolean
  * Default: false
  * Importance: low

`value.converter.value.schema.id.deserializer`
: The class name of the schema ID deserializer for values. This is used to deserialize schema IDs from the message headers.
  <br/>
  * Type: string
  * Default: io.confluent.kafka.serializers.schema.id.DualSchemaIdDeserializer
  * Importance: low

`value.converter.value.subject.name.strategy`
: Determines how to construct the subject name under which the value schema is registered with Schema Registry.
  <br/>
  * Type: string
  * Default: TopicNameStrategy
  * Importance: low

### Auto-restart policy

`auto.restart.on.user.error`
: Enable connector to automatically restart on user-actionable errors.
  <br/>
  * Type: boolean
  * Default: true
  * Importance: medium

## Frequently asked questions

Find answers to frequently asked questions about the DataStax Sink
connector for Confluent Cloud.

### When to choose Apache Cassandra or DSE versus DataStax Astra?

Set `deployment.type` to `Apache Cassandra or DSE` when you connect to
a self-managed Apache Cassandra or DSE cluster using contact points, with
optional SSL/TLS. Set it to `DataStax Astra` when you connect to an
Astra DB database using an uploaded SCB. The two modes
are mutually exclusive.

### Why does the connector fail with a missing keyspace or table error?

The connector does not create keyspaces, tables, or UDTs. Create the
target schema in your Cassandra, DSE, or Astra DB database before you
start the connector, then confirm that each entry in `mapping.map`
references an existing keyspace and table.

### Can I use a custom Cassandra Query Language (CQL) query instead of the auto-generated INSERT?

Yes, using the `query` per-table override. Use
this option only for idempotent statements. Because the connector provides
at-least-once delivery, a conditional write such as `IF NOT EXISTS` or a
counter update can apply more than once on retry.

## Next Steps

For an example that shows fully managed Confluent Cloud connectors in action with
Confluent Cloud for Apache Flink, see the [Cloud ETL Demo](/platform/current/tutorials/examples/cloud-etl/docs/index.html).
This example also shows how to use Confluent CLI to manage your resources in
Confluent Cloud.

[![image](images/topology.png)](https://docs.confluent.io/platform/current/tutorials/examples/cloud-etl/docs/index.html)