ESX Virtualization

VMware ESXi, vSphere, VMware Backup, Hyper-V... how-to, videos....

Nakivo Backup and Replication - #1 Backup solution for Virtual, physical, cloud, NAS and SaaS

VCP-VVF Administrator Study Guide: Objective 2.3 – VMware Storage Fundamentals, Part 2: Describe Use Cases for VMware vSAN ESA or VMware vSAN OSA

By | Last Updated:

Shares

Welcome back to our VMware Certified Professional – VMware vSphere Foundation Administrator (2V0-16.25) study guide series! This section is part of the upcoming VCP-VVF Study Guide Page, which will be released as a PDF when completed—check it out at https://www.vladan.fr/vcp-vvf-administrator/. Today, we’re continuing with Objective 2.3 – VMware Storage Fundamentals, focusing on Given a scenario, describe the use cases for VMware vSAN ESA or VMware vSAN OSA. We follow the official VMware Blueprint for the exam – VMware vSphere Foundation Administrator (PDF).

VMware vSAN, a key component of VMware vSphere Foundation (VVF) 9.0, offers two architectures: Original Storage Architecture (OSA) and Express Storage Architecture (ESA), each suited to different workloads and environments. This objective is critical for the 2V0-16.25 exam, testing your ability to identify the appropriate vSAN architecture for specific scenarios. Building on our previous post (Objective 2.3, Part 1 on configuring vSphere storage), we’ll provide detailed explanations, practical use cases, and exam-focused tips using a realistic scenario, aligned with VMware’s official vSphere 9.0 documentation https://techdocs.broadcom.com/us/en/vmware-cis/vsphere/vsphere/9-0.html. Let’s get started and explore vSAN use cases!

Why vSAN ESA and OSA Matter

VMware vSAN is a software-defined storage solution that pools local disks across ESXi hosts to create a shared datastore, offering scalability, performance, and integration with vSphere features like HA and DRS. VVF 9.0 supports two vSAN architectures: OSA (Original Storage Architecture), which uses a hybrid or all-flash disk group model, and ESA (Express Storage Architecture), a newer, all-flash architecture optimized for modern hardware. Objective 2.3, Part 2, evaluates your ability to describe use cases for each architecture in scenarios involving performance, cost, or scalability requirements. We’ll cover the differences between OSA and ESA, their ideal use cases, and how to choose the right one, preparing you for the exam and real-world administration.

Scenario: Describing vSAN ESA and OSA Use Cases

Let’s use a typical exam scenario: A medium-sized business with a 4-host vSphere cluster (“VVF-Cluster”) running 10 VMs for a web application (configured in Objective 2.2) is planning to expand its storage infrastructure. The cluster is managed by vCenter 9.0 (IP: 192.168.1.20, hosts at 192.168.1.10-13) with vSphere HA and DRS enabled. The existing vSAN datastore (OSA, configured in Objective 2.2, Part 2) supports the VMs, but the business is evaluating two new projects: a high-performance database requiring low latency and a cost-sensitive file server with moderate performance needs. You must describe the use cases for vSAN ESA and OSA to determine the best fit for each project, considering hardware, performance, and cost. This scenario tests your ability to match vSAN architectures to specific requirements for the 2V0-16.25 exam.

Describing Use Cases for vSAN ESA and OSA

Understanding the use cases for vSAN ESA and OSA involves comparing their architectures, hardware requirements, and suitability for different workloads. Below is a detailed guide with explanations and considerations for the scenario, using the vSphere Client and documentation for VVF 9.0.1. Overview of vSAN OSA and ESA

vSAN Original Storage Architecture (OSA):

  • Architecture: Uses disk groups with one cache SSD and 1-7 capacity disks (HDDs for hybrid, SSDs for all-flash) per host.
  • Hardware Requirements: Minimum 3 hosts (4 recommended for redundancy), 1 SSD (cache), 1+ HDDs/SSDs (capacity), 1 GbE (10 GbE recommended).
  • Features: Supports hybrid (HDD+SSD) or all-flash configurations, RAID 1/5/6, deduplication, compression, and encryption.
  • Performance: Good for general-purpose workloads; cache SSD reduces latency for hybrid setups.
  • Cost: Lower cost for hybrid (HDD-based) deployments, higher for all-flash.

vSAN Express Storage Architecture (ESA):

  • Architecture: Eliminates disk groups, using a single storage pool of NVMe or high-performance SSDs per host, optimized for modern hardware.
  • Hardware Requirements: Minimum 4 hosts, NVMe or enterprise-grade SSDs (no HDDs), 25 GbE (10 GbE minimum), vSAN ESA-ready hardware (e.g., vSAN ReadyNodes).
  • Features: All-flash only, enhanced compression, adaptive RAID 5/6, native snapshots, and encryption.
  • Performance: Superior for high-performance workloads due to NVMe optimization and lower overhead.
  • Cost: Higher due to NVMe/SSD and networking requirements.

Key Differences:

  • OSA supports hybrid and all-flash; ESA is all-flash only.
  • ESA requires modern hardware (NVMe, 25 GbE); OSA works with older hardware.
  • ESA offers better performance and efficiency; OSA is more cost-effective for hybrid setups.

Study Tip: Memorize OSA vs. ESA hardware requirements and features for the exam. Review https://techdocs.broadcom.com/us/en/vmware-cis/vsphere/vsphere/9-0.html for vSAN architecture details.

2. Use Case 1: High-Performance Database (vSAN ESA)

Scenario Context: The business needs a high-performance database (e.g., SQL Server or Oracle) with low latency (<1 ms) and high IOPS for real-time analytics, supporting 5 VMs with 100 GB disks each.

Use Case for vSAN ESA:

Why ESA?:

  • Performance: ESA’s NVMe-optimized storage pool delivers ultra-low latency and high IOPS, ideal for database workloads requiring fast read/write operations.
  • Efficiency: Enhanced compression and adaptive RAID 5/6 reduce storage overhead, maximizing capacity for the 500 GB total VM storage.
  • Native Snapshots: ESA’s native snapshot capabilities improve backup/restore performance for database VMs.
  • Scalability: ESA supports scaling out (adding hosts) or up (adding NVMe drives) for future database growth.

Implementation:

  • Deploy a new 4-host ESA cluster (e.g., “DB-Cluster”) with vSAN ESA-ready hardware (NVMe SSDs, 25 GbE NICs).
  • Configure a vSAN storage policy: Failures to Tolerate (FTT)=1, RAID-6, Compression Enabled.
  • Navigate to Cluster → Configure → vSAN → Services → Enable vSAN (ESA).
  • Apply the policy to the 5 database VMs: VM → VM Policies → Edit VM Storage Policies.

Verification:

  • Check Cluster → Monitor → vSAN → Performance for latency (<1 ms) and IOPS.
  • Confirm policy compliance in VM → Summary → Storage Policy.

Scenario Example: Use vSAN ESA for the high-performance database, deploying a new 4-host cluster with NVMe SSDs and a RAID-6 policy to ensure low latency and redundancy.

Study Tip: Practice configuring vSAN ESA in a lab, focusing on NVMe requirements and storage policies. Understand why ESA suits high-performance workloads for exam questions.

3. Use Case 2: Cost-Sensitive File Server (vSAN OSA)

Scenario Context: The business needs a file server for 10 VMs (50 GB disks each) with moderate performance requirements, prioritizing low cost over high performance.

Use Case for vSAN OSA:

Why OSA?:

Cost: OSA’s hybrid configuration (HDDs for capacity, SSD for cache) reduces hardware costs compared to ESA’s all-NVMe requirement.
Performance: Adequate for file server workloads with moderate IOPS (e.g., file sharing, archival), leveraging SSD cache for read/write acceleration.
Flexibility: OSA supports both hybrid and all-flash, allowing upgrades to all-flash later if needed.
Compatibility: Works with existing hardware (e.g., 1 GbE, older SSDs/HDDs), reducing infrastructure upgrades.

Implementation:

Use the existing “VVF-Cluster” (4 hosts, configured with OSA in Objective 2.2, Part 2) with 1 SSD (400 GB cache) and 2 HDDs (1 TB each) per host.
Configure a vSAN storage policy: FTT=1, RAID-1, Thin Provisioning.
Apply the policy to the 10 file server VMs: VM → VM Policies → Edit VM Storage Policies.

Verification:

Check Cluster → Monitor → vSAN → Health to ensure disk group health.
Monitor performance in Cluster → Monitor → vSAN → Performance for acceptable latency (e.g., <5 ms).

Scenario Example: Use vSAN OSA on the existing “VVF-Cluster” with a hybrid setup (HDD+SSD) and RAID-1 policy for the cost-sensitive file server VMs, ensuring low cost and sufficient performance.

Study Tip: Practice configuring vSAN OSA in a lab, comparing hybrid vs. all-flash setups. Understand cost-performance trade-offs for exam scenarios.

4. Comparing OSA and ESA in the Scenario

Decision Framework:

Database (High-Performance):

  • Choose vSAN ESA for its NVMe-optimized performance, low latency, and advanced features like adaptive RAID and compression.
  • Requires investment in NVMe SSDs and 25 GbE networking but ensures <1 ms latency for the database.

File Server (Cost-Sensitive):

  • Choose vSAN OSA for its lower cost (hybrid HDD+SSD) and compatibility with existing hardware, meeting moderate performance needs.
  • Leverages the existing “VVF-Cluster” without requiring hardware upgrades.

Considerations:

  • Hardware: ESA requires modern, vSAN ESA-ready hardware; OSA supports legacy hardware.
  • Cost vs. Performance: ESA is costlier but faster; OSA is budget-friendly for less demanding workloads.
  • Scalability: Both support scaling out, but ESA’s single-tier architecture simplifies management.
  • VVF 9.0 Support: VVF 9.0 supports both OSA and ESA, but ESA requires specific licensing (check VMware documentation for details).

Verification:

  • For ESA, verify performance in DB-Cluster → Monitor → vSAN → Performance.
  • For OSA, confirm health and capacity in VVF-Cluster → Monitor → vSAN → Health.

Study Tip: Memorize the decision criteria (performance, cost, hardware) for choosing OSA vs. ESA. Practice comparing use cases in a lab for the exam.

Exam Scenarios and Tips

Scenarios:

Scenario: A company needs storage for a low-latency analytics workload. Which vSAN architecture is best?
Answer: vSAN ESA, due to its NVMe-optimized performance and low latency.

Scenario: A small business with legacy hardware wants cost-effective storage. Which architecture fits?
Answer: vSAN OSA, supporting hybrid HDD+SSD setups for lower cost.

Scenario: A vSAN deployment fails due to hardware incompatibility. What’s a likely issue?
Answer: ESA requires NVMe SSDs and vSAN ESA-ready hardware; OSA may be needed for older hardware.

Study Tips:

Resources:

Sample Exam Questions

Which vSAN architecture supports hybrid HDD+SSD configurations?
A. vSAN ESA
B. vSAN OSA
C. Both ESA and OSA
D. Neither ESA nor OSA
Answer: B. vSAN OSA.

What is a key requirement for vSAN ESA in VVF 9.0?
A. 1 GbE networking
B. NVMe SSDs
C. Hybrid disk groups
D. 3-host minimum
Answer: B. NVMe SSDs.

Which workload is best suited for vSAN ESA?
A. Cost-sensitive file server
B. High-performance database
C. Legacy application with HDDs
D. General-purpose backup
Answer: B. High-performance database.

Final Words

Describing use cases for vSAN ESA and OSA is a vital skill for the 2V0-16.25 exam and VVF administration. By understanding their performance, cost, and hardware differences, you’ll choose the right architecture for any scenario. The upcoming VCP-VVF Study Guide Page, available at https://www.vladan.fr/vcp-vvf-administrator/, will be released as a PDF to support your preparation. Stay tuned for the next part of Objective 2.3! Happy studying, and good luck on your VCP-VVF journey!

More posts from ESX Virtualization:

Shares
5/5 - (1 vote)

About Vladan SEGET

This website is maintained by Vladan SEGET. Vladan is as an Independent consultant, professional blogger, vExpert x16, Veeam Vanguard x9, VCAP-DCA/DCD, ESX Virtualization site has started as a simple bookmarking site, but quickly found a large following of readers and subscribers.

Connect on: Facebook. Feel free to network via Twitter @vladan.

Leave a Reply

Your email address will not be published. Required fields are marked *