Apache Spark Certification Practice Test

In Apache Spark, the master URL is a critical piece of configuration that specifies the cluster manager to connect to. Each type of cluster manager has its own URL format.

The correct choice highlights that “http://host:port” is not a valid master URL option in Spark. This format signifies an HTTP protocol, typically used for web communication, but it does not align with any of the expected configurations for specifying a Spark cluster manager. The master URL is meant to indicate how the Spark application should connect to the cluster, which is not defined using HTTP links.

In contrast, the other options provided are valid configurations for the master URL:

- "local[*]" indicates that Spark should run in local mode using all available cores.

- "spark://host:port" refers to using Spark's standalone cluster manager, where 'host' is the server running the Spark master and 'port' is the communication port.

- "yarn-cluster" specifies that Spark should run on Apache Hadoop YARN in cluster mode, utilizing the YARN resource manager.

Therefore, the choice of “http://host:port” does not match the correct format required for a Spark master URL, highlighting why it is the correct answer to the question.