Configuring SSL for client-to-node connections

Use SSL to secure connections from a client node to the coordinator node.

Client-to-node encryption protects in-flight data from client machines to a database cluster using SSL (Secure Sockets Layer) and establishes a secure channel between the client and the coordinator node.

Complete the following procedure on every node in the cluster to configure SSL for client-to-node connections.

Note: On a DSE Search node, enabling SSL for the database automatically enables SSL in the DSE Search web.xml file and configures an SSL connector in Tomcat using the authentication/authorization filters. No changes are required for the web.xml or server.xml files.

If the TomcatSolrRunner doesn't find a connector in server.xml, it creates a default connector. The default connector binds to the .

CAUTION: If you are not using the JCE Unlimited Strength Jurisdiction Policy, make sure that your ticket granting principal does not use AES-256. If your ticket granting principal uses AES-256, you might see a warning like this in the logs:
WARN [StreamConnectionEstablisher:18] 2015-06-22 14:12:18,589 (line 162) Filtering out 
                    TLS_DHE_RSA_WITH_AES_256_CBC_SHA,TLS_RSA_WITH_AES_256_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA as it isnt supported by the socket


The location of the cassandra.yaml file depends on the type of installation:
Package installations /etc/dse/cassandra/cassandra.yaml
Tarball installations installation_location/resources/cassandra/conf/cassandra.yaml


The default location of the Tomcat server.xml file depends on the installation type:
Package installations /etc/dse/tomcat/conf/server.xml
Tarball installations installation_location/resources/tomcat/conf/server.xml


Create SSL certificates, keystores, and truststores. You can either create local keystore files or use a remote keystore provider.


  1. Edit cassandra.yaml and make the following changes in the client_encryption_options to enable SSL:
    1. Set enabled to true to enable SSL.
    2. Set optional to false (default) to only allow SSL connections.
    3. Set require_client_auth to true to require two-way host certificate validation.
  2. Configure the keystore and truststore. All settings are configured in the client_encryption_options section of cassandra.yaml:
    • Local files: use the following settings.
          enabled: true
          optional: false
          keystore: path_to_keystore
          keystore_password: keystore_password
          require_client_auth: true
          truststore_type: JKS
          truststore: path_to_truststore
          truststore_password: truststore_password
          protocol: ssl
          algorithm: SunX509
          store_type: JKS
          cipher_suites: [TLS_RSA_WITH_AES_128_CBC_SHA]
    Whether to enable client-to-node encryption.

    Default: false

    When optional is selected, both encrypted and unencrypted connections over native transport are allowed. That is a necessary transition state to facilitate enabling client to node encryption on live clusters without inducing an outage for existing unencrypted clients. Typically, once existing clients are migrated to encrypted connections, optional is unselected in order to enforce native transport encryption.

    Default: false

    Valid types are JKS, JCEKS and PKCS12. For file-based keystores, use PKCS12.
    Note: PKCS11 is not supported.

    Default: commented out (JKS)

    Relative path from DSE installation directory or absolute path to the Java keystore (JKS) suitable for use with Java Secure Socket Extension (JSSE), which is the Java version of the Secure Sockets Layer (SSL), and Transport Layer Security (TLS) protocols. The keystore contains the private key used to encrypt outgoing messages.

    Default: resources/dse/conf/.keystore

    Password for the keystore.

    Default: cassandra

    Whether to enable certificate authentication for client-to-node encryption. When not set, the default is false.
    Note: When set to true, client certificates must be present on all nodes in the cluster.

    Default: commented out (false)

    Valid types are JKS, JCEKS, and PKCS12.
    Attention: PKCS11 is not supported. Also, due to an OpenSSL issue, you cannot use a PKCS12 truststore that was generated via OpenSSL. For example, a truststore generated via the following command will not work with DSE:
    openssl pkcs12 -export -nokeys -out truststore.pfx -in intermediate.chain.pem
    However, truststores generated via Java's keytool and then converted to PKCS12 work with DSE. Example:
    keytool -importcert -alias rootca -file rootca.pem -keystore truststore.jks
    keytool -importcert -alias intermediate -file intermediate.pem -keystore truststore.jks
    keytool -importkeystore -srckeystore truststore.jks -destkeystore truststore.pfx -deststoretype pkcs12 

    Default: commented out (JKS)

    Relative path from DSE installation directory or absolute path to truststore containing the trusted certificate for authenticating remote servers.

    Default: resources/dse/conf/.truststore

    Password for the truststore. This must match the password used when generating the keystore and truststore.
    Note: Truststore password and path is only required when require_client_auth is set to true.

    Default: cassandra

  3. Save and close the cassandra.yaml file.
  4. Complete a rolling DSE restart.