Connect
Self-Managed Only

cassandra

Executes a find query and creates a message for each row received.

Introduced in version 4.10.0.

  • Common

  • Advanced

input:
  label: ""
  cassandra:
    addresses: [] # No default (required)
    timeout: 600ms
    reconnect_interval: 60s
    query: "" # No default (required)
    auto_replay_nacks: true
input:
  label: ""
  cassandra:
    addresses: [] # No default (required)
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    password_authenticator:
      enabled: false
      username: ""
      password: ""
    disable_initial_host_lookup: false
    max_retries: 3
    backoff:
      initial_interval: 1s
      max_interval: 5s
    timeout: 600ms
    host_selection_policy:
      local_dc: "" # No default (optional)
      local_rack: "" # No default (optional)
    reconnect_interval: 60s
    exponential_reconnection:
      max_retries: 0 # No default (required)
      initial_interval: "" # No default (required)
      max_interval: "" # No default (required)
    query: "" # No default (required)
    auto_replay_nacks: true

Examples

Minimal Select (Cassandra/Scylla)

Let’s presume that we have 3 Cassandra nodes, like in this tutorial by Sebastian Sigl from freeCodeCamp:

https://www.freecodecamp.org/news/the-apache-cassandra-beginner-tutorial/

Then if we want to select everything from the table users_by_country, we should use the configuration below. If we specify the stdin output, the result will look like:

{"age":23,"country":"UK","first_name":"Bob","last_name":"Sandler","user_email":"bob@email.com"}

This configuration also works for Scylla.

input:
  cassandra:
    addresses:
      - 172.17.0.2
    query:
      'SELECT * FROM learn_cassandra.users_by_country'

Fields

addresses[]

A list of Cassandra nodes to connect to. Multiple comma separated addresses can be specified on a single line.

Type: array<string>

# Examples:
addresses:
  - "localhost:9042"

# ---

addresses:
  - "foo:9042"
  - "bar:9042"

# ---

addresses:
  - "foo:9042,bar:9042"

auto_replay_nacks

Whether to automatically replay rejected messages (negative acknowledgements, or nacks) at the output level. If the cause of rejections persists, leaving this option enabled can result in back pressure.

Set auto_replay_nacks to false to delete rejected messages. Disabling auto replays can greatly improve memory efficiency of high throughput streams, as the original shape of the data is discarded immediately upon consumption and mutation.

Requires version 4.27.0 or later.

Type: bool

Default: true

backoff

The backoff the Cassandra driver applies between retries of a failed query.

Type: object

backoff.initial_interval

The period to wait before the first retry of a failed query. Each later retry doubles the previous wait, with random jitter of up to half this value, until backoff.max_interval is reached.

Type: string

Default: 1s

backoff.max_interval

The longest wait between retries of a failed query.

Type: string

Default: 5s

disable_initial_host_lookup

If enabled the driver will not attempt to get host info from the system.peers table. This can speed up queries but will mean that data_centre, rack and token information will not be available.

Type: bool

Default: false

exponential_reconnection

Configure exponential backoff for reconnection attempts to DOWN nodes. When enabled, this replaces the driver’s default constant reconnection policy with an exponential backoff strategy that gradually increases the delay between reconnection attempts. This reduces connection storm scenarios during widespread outages while ensuring eventual recovery.

Requires version 4.66.0 or later.

Type: object

exponential_reconnection.initial_interval

The initial period to wait between retry attempts.

Type: string

exponential_reconnection.max_interval

The longest wait between reconnection attempts to a node marked as DOWN.

Type: string

exponential_reconnection.max_retries

The maximum number of retry attempts.

Type: int

host_selection_policy

Advanced host selection policy settings for Cassandra clusters, highly recommended in multi-datacenter (DC) deployments. Use these options to optimize query routing in multi-DC and multi-rack deployments. By specifying a local DC and rack, you can use the DC-aware and rack-aware policies to direct queries to the closest nodes, reducing latency and improving fault tolerance. If not set, the default policy is round-robin across all available nodes. Host selection is always token-aware if the token can be calculated from the query.

Requires version 4.61.0 or later.

Type: object

# Examples:
host_selection_policy:
  local_dc: dc-east
  local_rack: rack1

host_selection_policy.local_dc

The name of the local datacenter to prioritize for query routing. Enables DC-aware host selection, ensuring queries are sent to nodes within this datacenter whenever possible. Recommended for clusters spanning multiple datacenters to minimize cross-DC traffic.

Type: string

host_selection_policy.local_rack

The name of the local rack to prioritize for query routing. Requires local_dc to be set. Enables rack-aware host selection, further optimizing query placement within the specified datacenter. Useful for deployments with multiple racks per datacenter to improve resilience and reduce intra-DC latency.

Type: string

max_retries

The maximum number of retries before giving up on a request.

Type: int

Default: 3

password_authenticator

Optional configuration of Cassandra authentication parameters.

Type: object

password_authenticator.enabled

Whether to use password authentication

Type: bool

Default: false

password_authenticator.password

The password to authenticate with.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

password_authenticator.username

The username to authenticate as.

Type: string

Default: ""

query

A query to execute.

Type: string

reconnect_interval

The interval at which Redpanda Connect attempts to reconnect to Cassandra nodes that are marked as DOWN. This setting helps maintain connectivity in unstable network conditions or during node maintenance. Use Go duration format such as 30s, 1m, or 5m. Setting this too low may create unnecessary connection attempts, while setting it too high may delay recovery from network issues.

Requires version 4.66.0 or later.

Type: string

Default: 60s

timeout

The client connection timeout.

Type: string

Default: 600ms

tls

Configure Transport Layer Security (TLS) settings to secure network connections. This includes options for standard TLS as well as mutual TLS (mTLS) authentication where both client and server authenticate each other using certificates. Key configuration options include enabled to enable TLS, client_certs for mTLS authentication, root_cas/root_cas_file for custom certificate authorities, and skip_cert_verify for development environments.

Requires version 4.25.0 or later.

Type: object

tls.client_certs[]

A list of client certificates for mutual TLS (mTLS) authentication. Configure this field to enable mTLS, authenticating the client to the server with these certificates.

You must set tls.enabled: true for the client certificates to take effect.

Certificate pairing rules: For each certificate item, provide either:

  • Inline PEM data using both cert and key or

  • File paths using both cert_file and key_file.

Mixing inline and file-based values within the same item is not supported.

Type: array<object>

Default: []

# Examples:
client_certs:
  - cert: foo
    key: bar


# ---

client_certs:
  - cert_file: ./example.pem
    key_file: ./example.key

tls.client_certs[].cert

The plaintext certificate to use for TLS authentication. Must be paired with the corresponding private key in the key field when using inline PEM data for mTLS client certificates.

Type: string

Default: ""

tls.client_certs[].cert_file

The path to a file containing the certificate to use for TLS authentication. Must be paired with the corresponding private key file in the key_file field when using file-based configuration for mTLS client certificates.

Type: string

Default: ""

tls.client_certs[].key

Private key for mTLS client certificate as inline PEM data. Must correspond to the client certificate specified in the cert field. Use this field together with cert when providing certificate data inline rather than through files.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

tls.client_certs[].key_file

Path to private key file for mTLS client certificate in PEM format. Must correspond to the client certificate specified in the cert_file field. Use this field together with cert_file when loading certificate data from files.

Type: string

Default: ""

tls.client_certs[].password

The password to use for the private key (specified in the key or key_file fields), if it is password-protected. The PKCS#1 and PKCS#8 formats are supported. Supports environment variable interpolation for secure password management.

The pbeWithMD5AndDES-CBC algorithm is obsolete and not supported for the PKCS#8 format. This algorithm does not authenticate the ciphertext, making it vulnerable to padding oracle attacks that can let an attacker recover the plaintext.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

# Examples:
password: foo

# ---

password: ${KEY_PASSWORD}

tls.enable_renegotiation

Whether to allow the remote server to repeatedly request renegotiation. Enable this option if you’re seeing the error message local error: tls: no renegotiation.

Type: bool

Default: false

tls.enabled

Whether to enable TLS for secure connections. Set to true to enable TLS encryption. Required to be true for other TLS options (like client_certs, root_cas, etc.) to take effect.

Type: bool

Default: false

tls.root_cas

Specify a root certificate authority to use (optional). This is a string that represents a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate. Use either this field for inline certificate data or root_cas_file for file-based certificate loading.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

# Examples:
root_cas: |-
  -----BEGIN CERTIFICATE-----
  ...
  -----END CERTIFICATE-----

tls.root_cas_file

Specify the path to a root certificate authority file (optional). This is a file, often with a .pem extension, which contains a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate. Use either this field for file-based certificate loading or root_cas for inline certificate data.

Type: string

Default: ""

# Examples:
root_cas_file: ./root_cas.pem

tls.skip_cert_verify

Whether to skip server-side certificate verification. Set to true only for testing environments as this reduces security by disabling certificate validation. When using self-signed certificates or in development, this may be necessary, but should never be used in production. Consider using root_cas or root_cas_file to specify trusted certificates instead of disabling verification entirely.

Type: bool

Default: false