CV0-004 Cloud Architecture and Design Practice Question
A company is designing an auto-scaling solution for a stateless application. Which TWO features are essential for the application to scale horizontally without issues? (Select TWO.)
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
✓
Stateless application design
Horizontal scaling requires that the application is stateless, meaning no session data is stored locally on instances, so any instance can handle any request. A load balancer is essential to distribute incoming traffic across multiple instances, ensuring no single instance is overwhelmed and that requests can be sent to any available instance. In contrast, stateful session management (B) and local storage (C) would tie data to specific instances, preventing seamless scaling. Vertical scaling (D) is about increasing resources of existing instances, not adding more instances horizontally.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Stateless application design
Why this is correct
Stateless application design ensures no session or local data persists on individual instances, so any instance can handle any request. This removes the need for sticky sessions or instance-specific state, directly enabling horizontal scaling and safe termination during scale-in events.
- ✗
Stateful session management
Why it's wrong here
Stateful sessions pin a client to one instance, so requests routed to new replicas lose session context and scaling fails. It is tempting because sticky sessions solve affinity for legacy apps, but stateless horizontal scaling demands externalised session state in a shared store like Redis.
- ✗
Use of local storage for application data
Why it's wrong here
Local storage ties each instance's data to that host, so a new replica cannot read it and scaling breaks. It is tempting because local disks are fast and simple for single-instance workloads, but horizontal scaling requires shared or external storage such as object storage or a network file system.
- ✗
Vertical scaling on the existing instances
Why it's wrong here
Vertical scaling adds CPU or memory to existing instances; it does not add replicas, so it cannot deliver horizontal scale-out. It is tempting because resizing an instance is quick and needs no code changes, but the stem explicitly asks for horizontal scaling of a stateless application.
- ✓
A load balancer to distribute traffic
Why this is correct
A load balancer distributes incoming traffic across all scaled instances and performs health checks, routing around failed nodes. This satisfies horizontal scaling by ensuring requests reach healthy instances without client awareness of individual instance addresses, complementing the stateless design requirement.
Go deeper
Related to this question
About these practice questions
Courseiva writes every CV0-004 question from scratch — 834 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 by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CV0-004 practice question is part of Courseiva's free CompTIA 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 CV0-004 exam.