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Difficulty: MediumBlob, File, and Disk Storage Solutions

A financial services company is migrating an on-premises database workload to Azure Virtual Machines. You are designing the storage configuration for the database transaction logs, which require consistent high write throughput and single-digit millisecond latency. The storage design must also ensure that the database remains operational even if a single datacenter within the target Azure region experiences a power failure. Which storage option should you recommend?

  1. Premium SSD Managed Disks configured with Zone-Redundant Storage (ZRS)Answer
  2. B
    Premium SSD Managed Disks configured with Locally Redundant Storage (LRS)
  3. C
    Standard SSD Managed Disks configured with Zone-Redundant Storage (ZRS)
  4. D
    Standard HDD Managed Disks configured with Locally Redundant Storage (LRS)

Answer

Premium SSD Managed Disks configured with Zone-Redundant Storage (ZRS)
The correct option is Premium SSD Managed Disks configured with Zone-Redundant Storage (ZRS). Database transaction logs are highly sensitive to latency and write performance, necessitating Premium SSD storage to guarantee single-digit millisecond latencies and high throughput. Furthermore, to survive the outage of a single datacenter (which corresponds to an Azure Availability Zone) without losing access to data, the disks must use Zone-Redundant Storage (ZRS) to replicate data synchronously across multiple zones in the region.

Step-by-Step Solution

1
Analyze the performance requirements of the workload.
The workload is a database transaction log requiring consistent high write throughput and single-digit millisecond latency.
This performance tier requires at least Premium SSD (or Premium SSD v2/Ultra Disk) because Standard SSD and Standard HDD do not offer the necessary IOPS, throughput, or latency guarantees.
2
Analyze the high availability and resiliency requirements.
The storage solution must remain operational during a single datacenter (zone) power failure.
This requirement mandates Zone-Redundant Storage (ZRS), which replicates data synchronously across three availability zones in the region. Locally Redundant Storage (LRS) only replicates within a single datacenter and is insufficient.
3
Combine performance and redundancy requirements to select the optimal disk configuration.
Premium SSD Managed Disks with Zone-Redundant Storage (ZRS) meets both the latency/throughput needs and the zone outage resiliency requirements.
Selecting Premium SSD ensures database logs perform optimally, and ZRS ensures zone-level redundancy.

Key Concept

Selecting Azure Managed Disk tiers and redundancy configurations based on workload performance and high availability requirements.
Estimated Time:1m 30s
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Topics

Blob, File, and Disk Storage Solutions

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