AZ-104 Implement and Manage Storage Practice Question
A finance application stores monthly invoice PDFs in Azure Blob Storage. The business wants the data to remain available if one availability zone in the region becomes unavailable, but it does not require a secondary region for read access. Which redundancy option should the administrator choose?
⚠ Common exam trap
Watch out — candidates often confuse ZRS with LRS, assuming that three copies in a single datacenter (LRS) are sufficient for zone-level resilience, when in fact LRS does not span availability zones and offers no protection against a full zone outage.
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
✓
ZRS, because it replicates data across zones in the same region and stays available through a zone outage.
B is correct because Zone-Redundant Storage (ZRS) synchronously replicates data across three Azure availability zones within the same region, ensuring that if one zone becomes unavailable, the data remains accessible from the other zones. This meets the business requirement of staying available during a zone outage without needing a secondary region for read access.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
LRS, because it keeps three copies within a single datacenter and is the least expensive option.
Why it's wrong here
Locally redundant storage (LRS) maintains three synchronous copies of the data within a single physical datacenter, guarding against disk and node failures but not against the loss of the entire datacenter or the availability zone that contains it. Because your stated requirement is to remain available through an availability zone outage, LRS is inadequate — a zone failure would take down every copy of the invoice PDFs. Though LRS is the least expensive option, cost does not compensate for failing the core resilience requirement.
When this WOULD be correct
A question requiring the lowest-cost redundancy option with no zone or region outage requirement, e.g., 'Which redundancy option minimizes cost for non-critical data that can be recreated?'
- ✓
ZRS, because it replicates data across zones in the same region and stays available through a zone outage.
Why this is correct
Zone-redundant storage (ZRS) synchronously replicates your invoice PDFs across three distinct availability zones within the same region, so if any single zone suffers an outage, the data remains available and no downtime occurs. This directly satisfies the requirement to survive a zone failure while keeping the design simple by avoiding a secondary region. Unlike LRS, ZRS prevents zone-level data loss; unlike GRS or RA-GRS, it does so without cross-region replication overhead.
- ✗
GRS, because it keeps a readable copy in the paired region and is always the best choice for resilience.
Why it's wrong here
Geo-redundant storage (GRS) asynchronously replicates data to a paired secondary region, providing protection against region-wide disasters, but it does not make the storage account available during an availability zone outage in the primary region — the primary endpoint remains down and writes cannot proceed. The claim that GRS is 'always the best choice' is incorrect because this scenario only asks for zone-level resilience in the same region, and GRS introduces unnecessary cross-region latency and complexity without directly addressing zone failures.
When this WOULD be correct
A question that requires data to remain available even if an entire region becomes unavailable, and the business needs a secondary region for disaster recovery without requiring immediate read access to the secondary copy.
- ✗
RA-GRS, because it provides read access to the secondary region and is required for zone-level resilience.
Why it's wrong here
Read-access geo-redundant storage (RA-GRS) adds a readable endpoint in the paired secondary region on top of GRS, but that read access is unrelated to surviving an availability zone outage in the primary region — the primary write endpoint is still vulnerable to a zone failure. The requirement does not call for secondary-region read availability; it only demands that the data remain available through a zone outage, which RA-GRS does not ensure because it is a geo-redundant feature, not a zone-redundant one. Zone-level resilience is provided by ZRS, not by RA-GRS.
When this WOULD be correct
RA-GRS would be correct if the question required both zone-level resilience within a region AND read access to a secondary region for disaster recovery or compliance purposes, such as when auditors need read-only access to data in a geographically separate location.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The AZ-104 exam frequently reuses these exact scenarios with slightly different constraints.
✓ZRS, because it replicates data across zones in the same region and stays available through a zone outage.Correct answer▾
Why this is correct
Zone-redundant storage (ZRS) synchronously replicates your invoice PDFs across three distinct availability zones within the same region, so if any single zone suffers an outage, the data remains available and no downtime occurs. This directly satisfies the requirement to survive a zone failure while keeping the design simple by avoiding a secondary region. Unlike LRS, ZRS prevents zone-level data loss; unlike GRS or RA-GRS, it does so without cross-region replication overhead.
✗LRS, because it keeps three copies within a single datacenter and is the least expensive option.Wrong answer — click to see why▾
Why this is wrong here
LRS replicates data within a single datacenter, not across availability zones, so it cannot survive an entire zone outage.
★ When this WOULD be the correct answer
A question requiring the lowest-cost redundancy option with no zone or region outage requirement, e.g., 'Which redundancy option minimizes cost for non-critical data that can be recreated?'
Why candidates choose this
Candidates may think LRS is sufficient because it provides three copies, overlooking that all copies are in one zone and thus vulnerable to zone failure.
✗GRS, because it keeps a readable copy in the paired region and is always the best choice for resilience.Wrong answer — click to see why▾
Why this is wrong here
GRS replicates data to a paired secondary region, which is unnecessary because the question explicitly states that a secondary region is not required for read access. It also costs more than ZRS and does not provide zone-level resilience within the primary region.
★ When this WOULD be the correct answer
A question that requires data to remain available even if an entire region becomes unavailable, and the business needs a secondary region for disaster recovery without requiring immediate read access to the secondary copy.
Why candidates choose this
Candidates may think GRS is always the best for resilience, overlooking that the question specifies a single-region zone outage scenario, not a regional disaster.
✗RA-GRS, because it provides read access to the secondary region and is required for zone-level resilience.Wrong answer — click to see why▾
Why this is wrong here
RA-GRS provides read access to a secondary region, but the question explicitly states that a secondary region is not required. The requirement is only for zone-level resilience within the same region, which ZRS fulfills.
★ When this WOULD be the correct answer
RA-GRS would be correct if the question required both zone-level resilience within a region AND read access to a secondary region for disaster recovery or compliance purposes, such as when auditors need read-only access to data in a geographically separate location.
Why candidates choose this
Candidates may confuse RA-GRS with ZRS, thinking that the 'R' in RA-GRS stands for 'zone' or that read-access geo-redundancy automatically includes zone-level protection, when in fact RA-GRS does not replicate across zones within the primary region.
Analysis generated from the official AZ-104blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Quick reference
Azure Blob Storage Tier Comparison
| Tier | Storage Cost | Retrieval Cost | Latency | Use Case |
|---|---|---|---|---|
| Hot | Highest | Lowest | Immediate | Active data, frequent reads |
| Cool | Lower | Higher | Immediate | Data accessed < once / month |
| Cold | Lower still | Higher | Immediate | Data accessed < once / quarter |
| Archive | Lowest | Highest + rehydration delay | Hours | Long-term compliance retention |
Go deeper
Related to this question
Learn chapter
Managed Identities for Azure Resources
Key term
Region
A region is a distinct geographic location where a cloud provider operates multiple data centers that are connected by low-latency networks and provide cloud services.
Key term
Zone-redundant storage
Zone-redundant storage is a data replication method that stores copies of your data in multiple physical locations within a cloud region, so your data remains safe and available even if one entire data center fails.
About these practice questions
Courseiva writes every AZ-104 question from scratch — 1,049 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 AZ-104 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-104 exam.