AZ-305 Design infrastructure solutions Practice Question
A logistics company runs a customer-facing web application on 20 Azure VMs behind an Azure Standard Load Balancer. The company requires a 99.99% availability SLA for the VMs. The VMs are currently all deployed in a single availability set within one Azure region. What should you recommend to meet the SLA requirement with minimal architectural changes?
⚠ Common exam trap
The trap here is assuming that adding more availability sets or using a single placement group scale set automatically improves the SLA, when only availability zones provide the higher 99.99% SLA.
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
✓
Deploy the VMs across three availability zones in the same region.
Availability zones are physically separate datacenters within an Azure region, each with independent power, cooling, and networking. Deploying VMs across three zones provides a 99.99% SLA, higher than the 99.95% offered by availability sets. This approach requires minimal changes because the existing load balancer can be made zone-redundant, and no cross-region data replication is needed.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Deploy the VMs across multiple regions and use Azure Traffic Manager for load balancing.
Why it's wrong here
While multi-region deployment can improve availability, it introduces significant architectural complexity, including cross-region networking, data replication, and traffic management. The scenario asks for minimal changes and a 99.99% SLA, which can be achieved within a single region using availability zones. Multi-region is overkill and not minimal.
- ✓
Deploy the VMs across three availability zones in the same region.
Why this is correct
Availability zones provide a higher SLA (99.99%) for VMs because they are physically separate datacenters within a region, protecting against datacenter-level failures. Deploying the existing VMs across three zones in the same region meets the SLA with minimal changes to the overall architecture, as the load balancer can be zone-redundant.
- ✗
Keep the VMs in the availability set but add a second availability set in the same region.
Why it's wrong here
Availability sets only provide a 99.95% SLA. Adding another availability set does not change the SLA because each VM belongs to only one availability set. The SLA is per VM, so this approach does not meet the 99.99% requirement. Availability sets protect against hardware failures but not datacenter failures.
- ✗
Move the VMs to Azure Virtual Machine Scale Sets with a single placement group.
Why it's wrong here
Virtual Machine Scale Sets with a single placement group are limited to 100 VMs and still reside within a single availability set or zone. A single placement group does not provide zone redundancy, so the SLA remains at 99.95% unless the scale set is configured for zone spanning. This does not meet the 99.99% SLA.
Go deeper
Related to this question
About these practice questions
One of 795 original AZ-305 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. 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 Microsoft exam blueprint
This AZ-305 practice question is part of Courseiva's free Microsoft 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 AZ-305 exam.