PCA Prometheus Fundamentals Practice Question
Which TSDB component is responsible for ensuring data durability if the server crashes?
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
✓
WAL (Write-Ahead Log)
The Write-Ahead Log (WAL) records incoming samples before they are committed to blocks.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Tombstone file
Why it's wrong here
Tombstone files track deleted data series.
- ✓
WAL (Write-Ahead Log)
Why this is correct
The WAL ensures that data in memory can be recovered after a crash.
- ✗
Head block
Why it's wrong here
The head block is in-memory and volatile.
- ✗
Index file
Why it's wrong here
The index file is for querying, not crash recovery.
About these practice questions
Courseiva writes every PCA question from scratch — 304 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or 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 August 2026 · checked against the official CNCF / Linux Foundation exam blueprint
This PCA practice question is part of Courseiva's free CNCF / Linux Foundation 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 PCA exam.