Databricks-Spark-Assoc Using Spark Connect Practice Question
You are troubleshooting a Spark Connect application that fails to connect to a Databricks cluster. The error message indicates an authentication failure. Which of the following is the most likely cause?
⚠ Common exam trap
The trap here is attributing an authentication failure to network or cluster state issues, when the error message explicitly points to credentials being the problem.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The personal access token (PAT) has expired or is invalid.
Authentication failures in Spark Connect are typically due to invalid credentials, such as an expired or incorrect personal access token. The token must be valid and have the necessary permissions to access the cluster. Other issues like network problems or cluster state would produce different error messages, making the token the primary suspect.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The client machine's firewall is blocking outbound connections on port 443.
Why it's wrong here
A firewall blocking port 443 would result in a connection timeout or network unreachable error, not an authentication failure. Authentication errors occur after a connection is established, so network issues would manifest differently. Thus, this is not the most likely cause.
- ✗
The Databricks cluster is not running or is in a terminated state.
Why it's wrong here
If the cluster is not running, the connection would fail with a network error or a message indicating the cluster is unavailable, not an authentication failure. Authentication occurs before the cluster state is checked. Therefore, this is not the most likely cause for an authentication error.
- ✓
The personal access token (PAT) has expired or is invalid.
Why this is correct
Authentication failures in Spark Connect often stem from invalid or expired credentials. The personal access token is used to authenticate the client to the Databricks workspace. If the token is expired, revoked, or incorrect, the server rejects the connection. Checking the token's validity and permissions is the first step in troubleshooting.
- ✗
The client is using an outdated version of the Spark Connect protocol.
Why it's wrong here
While protocol version mismatch can cause connection issues, the error specifically mentions authentication failure. An outdated protocol would typically result in a different error, such as unsupported method or handshake failure. Authentication failures are related to credentials, not protocol versions.
About these practice questions
This Databricks-Spark-Assoc question is part of Courseiva's 295-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Databricks exam blueprint
This Databricks-Spark-Assoc practice question is part of Courseiva's free Databricks certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the Databricks-Spark-Assoc exam.