Wildcard DNS Subdomain Requirement

When you first set up Cloudera Data Science Workbench, you are asked to create a wildcard DNS entry for the Cloudera Data Science Workbench domain. Cloudera Data Science Workbench uses these wildcard subdomains (*.cdsw.<your_domain>.com) to route HTTP requests to engines and services launched by users.

Every time users launch workloads (session/job/experiment/model) on Cloudera Data Science Workbench, a new engine is created for each workload. These engines are isolated Docker containers where users can execute code. Each engine is assigned its own unique, randomly-generated ID, which is saved to the CDSW_ENGINE_ID environment variables. This ID is also used to create a unique subdomain for each engine. These subdomains are of the form: <CDSW_ENGINE_ID>.cdsw.<your_domain>.com.

Assigning a unique subdomain to each engine allows Cloudera Data Science Workbench to:

• Securely expose interactive session services, such as visualizations, the terminal, and web UIs such as TensorBoard, Shiny, Plotly, and so on;

• Prevent cross-site scripting (XSS) attacks by securely isolating user-generated content from the Cloudera Data Science Workbench application.

It is important to note that because there is no limit to the number of workloads (i.e. engines) users can launch, Cloudera Data Science Workbench requires the ability to randomly generate large numbers of engine IDs (and their subdomains) on-demand. Therefore, creating a wildcard DNS subdomain is essential for Cloudera Data Science Workbench to function successfully.

Additionally, if you want to enable TLS for your deployment, your TLS certificate will need to include both, the Cloudera Data Science Workbench domain, as well as the wildcard for all first-level subdomains. This is required so that your browser can trust communications with the <CDSW_ENGINE_ID>.cdsw.<your_domain>.com subdomains.