AZ-104 Certification Notes

Chapter 8.7 - LRS ZRS

Replication and Data Redundancy

• Redundancy in the Primary Region

  • Data is replicated 3 times in the primary region
  • There are two options for storing in the primary region

• Locally Redundant Storage (LRS)

  • Copies data synchronously in primary region
  • 99.99% (11 nines) durability
  • Cheapest option

• Zone-redundant storage (ZRS)

  • Copies data synchronously across 3 AZs in a primary region
  • 99.99% (12 nines) durability

Practice Quiz

• Using the Redundancy in the Primary Region Tier, data is replicated 3 times in the primary region.

  • True
  • False

• What is Locally Redundant Storage (LRS)?

  • It copies data synchronously in primary region, it has 99.999999999% (11 nines) durability and is the cheapest option.

• Which option for storing in the primary region copies data synchronously across 3 AZs and it has 99.9999999999% (12 nines) durability?

  • Zone-redundant storage (ZRS)