Configuring TLS Encryption for Cloudera Manager Using Auto-TLS

Use Auto-TLS to simplify the process of configuring TLS encryption for Cloudera Manager.

Auto-TLS greatly simplifies the process of enabling and managing TLS encryption on your cluster. It automates the creation of an internal certificate authority (CA) and deployment of certificates across all cluster hosts. It can also automate the distribution of existing certificates, such as those signed by a public CA. Adding new cluster hosts or services to a cluster with auto-TLS enabled automatically creates and deploys the required certificates.

Auto-TLS Requirements and Limitations

  • You must install the Cloudera Manager Agent software on the Cloudera Manager Server host.
  • You can enable auto-TLS using certificates created and managed by a Cloudera Manager certificate authority (CA), or certificates signed by a trusted public CA or your own internal CA. If you want to use a trusted public CA or your own internal CA, you must obtain all of the host certificates before enabling auto-TLS. For instructions on obtaining certificates from a CA, see On Each Cluster Host:.

    The following services support auto-TLS:

    • Cloudera Manager Host Monitor Debug Interface
    • Cloudera Manager Service Monitor Debug Interface
    • HDFS Client Configuration
    • HDFS NameNode Web UI
    • HiveServer2
    • HttpFS
    • Hue Client
    • Hue Load Balancer
    • Hue Server
    • Impala Catalog Server
    • Impala Server
    • Impala StateStore
    • Kafka Broker Server
    • Oozie
    • Spark History Server
    • YARN Web UI

For unlisted services, you must enable TLS manually. See the applicable component guide for more information.

The certmanager Utility

Auto-TLS is managed using the certmanager utility, which is included in the Cloudera Manager Agent software, and not the Cloudera Manager Server software. You must install the Cloudera Manager Agent software on the Cloudera Manager Server host to be able to use the utility. You can use certmanager to manage auto-TLS on a new installation.

The certmanager syntax is as follows:

/opt/cloudera/cm-agent/bin/certmanager [OPTIONS] COMMAND [ARGS]...
  • Options:
    • --location <certmanager-dir-root>

      The directory where certmanager stores all of its files on the Cloudera Manager Server host. If omitted, defaults to /var/lib/cloudera-scm-server/certmanager. This directory is created automatically, and must not exist before running the command. If it does exist, you can use the --rotate argument (documented below) to back up the existing directory and create a new one in its place.

      The agent host certificates and other files are stored elsewhere on each agent (see Auto-TLS Agent File Locations).

    • --help

      Displays the help message.

  • Commands:
    • add_custom_cert

      Adds a custom certificate and key for a host. Use this command only if you have configured a custom certificate directory (using the setup_custom_certdir command). You must run this command before adding a host in Cloudera Manager.

    • export_ca_cert

      Displays the Cloudera Manager internal CA certificate. You can export the certificate to a file using a redirect operator (> or >>).

    • setup

      Initializes the certificate manager and the internal CA, and configures Cloudera Manager Server to enable auto-TLS.

      • --configure-services

        Configures Cloudera Manager Server to enable automatic configuration of TLS for supported components, such as HDFS, YARN, and so on. If you omit this option, auto-TLS will only be configured for Cloudera Manager agent/server communication.

      • --rotate

        Backs up the certmanager root directory (/var/lib/cloudera-scm-server/certmanager by default, or specified by the --location option) if it exists, and creates a new one in its place. If the directory does not exist, it is created. If the directory exists, and you do not use the --rotate argument, the command fails.

      • --override ca_dn="<CA_DN>"

        Overrides the default CA distinguished name (DN) with the provided DN. Use this if your environment requires that the common name (CN) matches the hostname. For example:

        --override ca_dn="CN=cm01,DC=example,DC=com"
      • --stop-at-csr

        Stops the setup process after generating the private key and certificate signing request (CSR) for an intermediate CA certificate, and outputs the CSR file location to the screen. Submit the provided CSR to your internal root CA for signing. After receiving the signed intermediate CA certificate, continue the setup using the --signed-ca-cert parameter.

        When using the --stop-at-csr and --signed-ca-cert arguments, make sure that the remaining command options and arguments are the same.

      • --signed-ca-cert=<intermediate_CA_cert>

        Resumes the setup process using the provided signed intermediate CA certificate.

        When using the --stop-at-csr and --signed-ca-cert arguments, make sure that the remaining command options and arguments are the same.

    • setup_custom_certdir

      Initializes the certificate manager using a custom certificate directory. Use this command if you are using existing certificates signed by a trusted public CA or your own internal CA.

      • --configure-services

        Configures Cloudera Manager Server to enable automatic configuration of TLS for supported components, such as HDFS, YARN, and so on. If you omit this option, auto-TLS will only be configured for Cloudera Manager agent/server communication.

      • --rotate

        Backs up the certmanager root directory (/var/lib/cloudera-scm-server/certmanager by default, or specified by the --location option) if it exists, and creates a new one in its place. If the directory does not exist, it is created. If the directory exists, and you do not use the --rotate argument, the command fails.

Rotating Auto-TLS Certificate Authority and Host Certificates

Your cluster security requirements may require that you rotate the auto-TLS CA and certificates.

  1. Navigate to Administration > Security. Click the Rotate Auto-TLS Certificates button to launch the wizard.
  2. Complete the wizard.

Auto-TLS Agent File Locations

The certificates, keystores, and password files generated by auto-TLS are stored in /var/lib/cloudera-scm-agent/agent-cert on each Cloudera Manager Agent. The filenames are as follows:

Table 1. Auto-TLS Agent Files
Filename Description
cm-auto-global_cacerts.pem CA certificate and other trusted certificates in PEM format
cm-auto-global_truststore.jks CA certificate and other trusted certificates in JKS format
cm-auto-in_cluster_ca_cert.pem CA certificate in PEM format
cm-auto-in_cluster_truststore.jks CA certificate in JKS format
cm-auto-host_key_cert_chain.pem Agent host certificate and private key in PEM format
cm-auto-host_cert_chain.pem Agent host certificate in PEM format
cm-auto-host_key.pem Agent host private key in PEM format
cm-auto-host_keystore.jks Agent host private key in JKS format
cm-auto-host_key.pw Agent host private key password file