Azure Storage Redundancy

Lesson: Describe Azure Storage Redundancy

Lesson Introduction

In this lesson, you'll learn about the various redundancy options available in Azure Storage. Redundancy is crucial for ensuring your data is protected from planned and unplanned events such as hardware failures, power outages, and natural disasters. Azure Storage offers multiple redundancy options to meet different availability and durability requirements.

Redundancy in the Primary Region

Azure Storage always replicates your data three times within the primary region to ensure durability and availability. There are two main redundancy options within the primary region:

Locally Redundant Storage (LRS)

Locally redundant storage (LRS) replicates your data three times within a single data center in the primary region. LRS offers at least 99.999999999% durability over a given year. While LRS protects against server rack and drive failures, it does not safeguard against data center disasters like fire or flooding.

Diagram: Locally Redundant Storage (LRS)

Datacenter	Storage Account Name	Data
Primary Region	myaccount1	Copy 1
myaccount1	Copy 2
myaccount1	Copy 3

Zone-Redundant Storage (ZRS)

For regions with Availability Zones, zone-redundant storage (ZRS) synchronously replicates your data across three Azure availability zones in the primary region. ZRS ensures that your data remains accessible even if one zone becomes unavailable, offering at least 99.9999999999% durability over a given year.

Diagram: Zone-Redundant Storage (ZRS)

Primary Region	Availability Zone 1	Availability Zone 2	Availability Zone 3
Datacenter	Storage Account	Storage Account	Storage Account
myaccount1	myaccount1	myaccount1
Copy 1	Copy 2	Copy 3

Redundancy in a Secondary Region

For applications requiring high durability, Azure Storage allows replication to a secondary region that is geogr…