Choosing the Right Azure Storage Redundancy: ZRS, GZRS, GRS
A workload uses Azure Blob Storage for customer uploads. The team wants protection against a datacenter failure within the primary region and wants data copied to a paired region for disaster recovery, but they do not need to read from the secondary region during normal operations. Which redundancy option fits best?
Quick Answer
The answer is GZRS, or Geo-Zone-Redundant Storage, because it uniquely combines synchronous replication across three Azure availability zones within the primary region—providing the required datacenter failure protection—with asynchronous geo-replication to a single paired region for disaster recovery, all without enabling read access to the secondary copy during normal operations. This directly satisfies the workload’s need for zone-level fault tolerance and regional backup while keeping secondary access inactive. On the AZ-104 exam, this scenario tests your understanding of how GZRS bridges the gap between ZRS (zone protection only) and GRS (regional protection without zone resilience); a common trap is choosing GRS, which lacks zone redundancy, or RA-GZRS, which adds unnecessary read access. To remember: think “GZRS = ZRS + GRS, but no read,” meaning you get both zone and geo protection, but the secondary stays offline until failover.
⚠ Common exam trap
Candidates often confuse GRS with GZRS, assuming GRS provides zone-level redundancy, but GRS only uses LRS in the primary region, leaving data vulnerable to a single datacenter failure within that region.
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
✓
GZRS
GZRS (Geo-Zone-Redundant Storage) is correct because it combines ZRS within the primary region (synchronously replicating data across three Azure availability zones) with asynchronous geo-replication to a paired secondary region. This provides protection against both a datacenter failure (via ZRS) and a full region failure (via geo-replication), while the lack of read access from the secondary during normal operations matches the requirement exactly.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
ZRS
Why it's wrong here
ZRS protects against a zone outage, but it does not replicate data to another region for disaster recovery.
When this WOULD be correct
A question where the requirement is to protect against a datacenter failure within a single region (e.g., an availability zone outage) and there is no need for cross-region replication. For example: 'A workload requires high availability within a single region and can tolerate a zone failure, but does not need geo-redundancy.'
- ✓
GZRS
Why this is correct
GZRS protects against zone failure and also replicates data to a paired region for disaster recovery.
- ✗
RA-GZRS
Why it's wrong here
RA-GZRS adds read access to the secondary region, which the team does not need in this requirement.
When this WOULD be correct
A scenario where the workload requires read access to the secondary region for high availability, such as serving read requests from the secondary during a regional outage, would make RA-GZRS correct.
- ✗
GRS
Why it's wrong here
GRS copies data to a paired region, but it does not provide zone-redundant protection in the primary region.
When this WOULD be correct
GRS would be correct if the question only required disaster recovery to a paired region without needing protection against a datacenter failure within the primary region, and the workload could tolerate potential data loss during a regional disaster.
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.
✓GZRSCorrect answer▾
Why this is correct
GZRS protects against zone failure and also replicates data to a paired region for disaster recovery.
✗ZRSWrong answer — click to see why▾
Why this is wrong here
ZRS replicates data synchronously across multiple availability zones within a single region, but does not copy data to a paired region for disaster recovery, failing to meet the requirement for protection against a datacenter failure in the primary region and cross-region DR.
★ When this WOULD be the correct answer
A question where the requirement is to protect against a datacenter failure within a single region (e.g., an availability zone outage) and there is no need for cross-region replication. For example: 'A workload requires high availability within a single region and can tolerate a zone failure, but does not need geo-redundancy.'
Why candidates choose this
Candidates may confuse ZRS with geo-redundant options because ZRS provides redundancy across zones, and they might overlook the requirement for cross-region disaster recovery to a paired region.
✗RA-GZRSWrong answer — click to see why▾
Why this is wrong here
RA-GZRS provides read access to the secondary region, but the question states they do not need to read from the secondary during normal operations, making GZRS (without read access) the correct choice.
★ When this WOULD be the correct answer
A scenario where the workload requires read access to the secondary region for high availability, such as serving read requests from the secondary during a regional outage, would make RA-GZRS correct.
Why candidates choose this
Candidates may confuse GZRS with RA-GZRS, thinking the 'read-access' feature is always beneficial, or they may overlook the explicit requirement that read access is not needed.
✗GRSWrong answer — click to see why▾
Why this is wrong here
GRS replicates data to a paired region for disaster recovery but does not provide protection against a datacenter failure within the primary region because it uses LRS locally. The question requires protection against a datacenter failure within the primary region, which GRS lacks.
★ When this WOULD be the correct answer
GRS would be correct if the question only required disaster recovery to a paired region without needing protection against a datacenter failure within the primary region, and the workload could tolerate potential data loss during a regional disaster.
Why candidates choose this
Candidates may confuse GRS with GZRS, thinking that GRS also provides zone-level redundancy within the primary region, or they may overlook the requirement for protection against a datacenter failure 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?”
Visual reference
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
Availability
Availability is the measure of how often a system or service is operational and accessible when needed, typically expressed as a percentage of uptime.
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 →
Same concept, more angles
3 more ways this is tested on AZ-104
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A finance team stores monthly reports in Azure Blob Storage. The data must remain available if one datacenter in the Azure region fails, but the company does not need read access from a secondary region. Which redundancy option should the administrator choose?
easy- A.Locally redundant storage (LRS)
- ✓ B.Zone-redundant storage (ZRS)
- C.Geo-redundant storage (GRS)
- D.Read-access geo-redundant storage (RA-GRS)
Why B: Zone-redundant storage (ZRS) replicates data synchronously across three Azure availability zones within a single region, ensuring durability even if one datacenter (zone) fails. Since the requirement specifies no need for read access from a secondary region, ZRS meets the high-availability need without the cost or complexity of geo-replication.
Variation 2. A finance team stores PDF statements in Azure Blob Storage. The workload must survive a zone failure in the primary region, and if the entire region becomes unavailable, auditors still need read-only access to the copies in the secondary region. Which redundancy option should you choose?
medium- A.ZRS, because it keeps copies across zones but does not replicate to another region.
- ✓ B.RA-GZRS, because it combines zone redundancy with geo-replication and read access to the secondary region.
- C.LRS, because it keeps three copies in a single datacenter and is sufficient for regional resilience.
- D.GRS, because it provides geo-replication and always allows direct reads from the secondary region.
Why B: RA-GZRS (Read-Access Geo-Zone-Redundant Storage) is the correct choice because it combines zone redundancy (synchronous replication across Azure availability zones within the primary region) with geo-replication (asynchronous replication to a secondary region), and crucially enables read access to the secondary region even when the primary is unavailable. This meets the requirement to survive a zone failure (via ZRS) and provide read-only access during a full regional outage (via the read-access geo-replication endpoint).
Variation 3. You are designing a disaster recovery strategy for Azure Blob Storage. The storage account is configured with geo-redundant storage (GRS). Which three of the following statements about GRS and failover are true? (Choose three.)
medium- .GRS guarantees zero data loss if a failover is triggered.
- ✓ .GRS provides three copies of your data within the primary region and three additional copies in the secondary region.
- ✓ .In the event of a regional outage, you can initiate a customer-managed failover to the secondary region.
- .Once a failover is completed, you cannot fail back to the original primary region.
- .After a failover, the secondary region becomes the new primary and replication to the original primary is automatically established.
- ✓ .With GRS, data is replicated asynchronously to a paired secondary region.
Why : Geo-redundant storage (GRS) replicates data asynchronously to a paired secondary region, ensuring durability even during a regional outage. In such an outage, you can initiate a customer-managed failover to promote the secondary region as the new primary. GRS maintains three copies (LRS) in the primary region and three additional copies in the secondary region, providing six total replicas.
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.