Cloudera Docs

Configuring TLS Encryption for Cloudera Manager Using Auto-TLS

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

The Auto-TLS feature automates all the steps required to enable TLS encryption at a cluster level. Using Auto-TLS, you can let Cloudera manage the Certificate Authority (CA) for all the certificates in the cluster or use the company’s existing CA. In most cases, all the necessary steps can be enabled easily via the Cloudera Manager UI. This feature automates the following processes –

When Cloudera Manager is used as a Certificate Authority:
  • Creates the root Certificate Authority or a Certificate Signing Request (CSR) for creating an intermediate Certificate Authority to be signed by company’s existing Certificate Authority (CA)
  • Generates the CSRs for hosts and signs them automatically
The following steps are always performed
  • Creates a keystore and truststore for hosts.
  • Deploys the certificates, keystore and truststore to all the hosts in the cluster.
  • All the cluster services are then automatically TLS enabled by configuring the keystore and truststore information from a role instance specific directory.
  • Enables TLS for Cloudera Manager server and agents.
  • After this initial setup, any new service, hosts (or) additional compute clusters setup are automatically TLS enabled by default.
  • Provides an automation framework for rotating certificates.
Let us review these options with examples below on a CDP Private Cloud Base 7.1 cluster:
  • Use case 1: Using Cloudera Manager to generate an internal CA and corresponding certificates
  • Use case 2: Enabling Auto-TLS with an existing Root CA
  • Use case 3: Enabling Auto-TLS with existing Certificates

New Cluster deployment

With either of these options, you can reuse the existing TLS settings when creating a new cluster on a Cloudera Manager with Auto-TLS enabled. When you launch the wizard to create a new cluster you should see the following message. Now, when you deploy the cluster, all services will be automatically configured with wire encryption.

Summary

The Auto-TLS functionality not only speeds up the initial setup of the wire encryption but also automates future TLS configuration steps for the cluster. The following table summarizes the differences between the available options.

Steps HDP/EDH (manual) CDP Private Cloud use case 1 - Using Cloudera Manager to generate an internal CA and corresponding certificates CDP Private Cloud use case 2 - Enabling Auto-TLS with an existing Root CA CDP Private Cloud use case 3 - Enabling Auto-TLS with Existing Certificates
Generate CSR Manual Automated Automated Manual
CSR Signed by CA Manual Automated One-time Manual
Deploy certificate to all hosts Manual Automated Automated Automated
Configuration for each service Manual Automated Automated Automated
Cluster restarts Multiple Once Once Once
Configuration steps Manual Automated Automated Automated
New Service steps Manual Automated Automated Automated
New Host cert. generation Manual Automated Automated Manual
The Auto-TLS feature significantly reduces the overhead of TLS management of your cluster, thus providing increased security with reduced operational overhead and helps you stay focused on your customers and their workloads.

Rotating Auto-TLS Certificate Authority and Host Certificates

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

Using an internal CA (Use case 1)

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

Using a custom CA (Use case 3)

  1. Use the /cm/commands/addCustomCerts API command to replace the old certificates with new certificates in CMCA directory for each host. You must run this command for each host separately. An example of a curl command to upload the certificates to Cloudera Manager : 
    curl -u admin:admin -X POST --header 'Content-Type:
application/json' --header 'Accept: application/json' -d '{
            "location": "/opt/cloudera/AutoTLS",
            "interpretAsFilenames": true,
            "hostCerts": [ {
                "hostname": "ccycloud-10.vcdp71.root.hwx.site",
                "certificate":
"/tmp/auto-tls/certs/ccycloud-10.vcdp71.root.hwx.site.pem",
            "key":
"/tmp/auto-tls/certs/ccycloud-10.vcdp71.root.hwx.site.pem"
            } ]
}' 'https://ccycloud-7.vcdp71.root.hwx.site:7183/api/v41/cm/commands/addCustomCerts'
    In the example above, the "location" should be omitted if Auto-TLS was enabled or rotated after 7.1, and the file paths should point to files on the CM server host.
  2. Use CM API /hosts/{hostId}/commands/generateHostCerts to deploy the new certificates to each host. You must run this command for each host separately. An example curl command : 
    curl -u admin:admin -X POST --header 'Content-Type: application/json' --header 
'Accept: application/json' -d '{ "sshPort" : 22, "userName" : "root", "password" : "cloudera" }' 
'https://ccycloud-7.vcdp71.root.hwx.site:7183/api/v41/hosts/250e1bb7-8987-419c-a53f-c852c275d299/commands/generateHostCerts'
    where '250e1bb7-8987-419c-a53f-c852c275d299' in the command above is the hostID.

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