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Comparing FA to vSAN for VCF Workload Domains

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The purpose of this document is to share how the Pure Storage FlashArray can enhance the capabilities of the VMware Cloud Foundation (VCF) suite. VCF is an integrated stack comprised of vSphere, vSAN, NSX, SDDC Manager, and the vRealize suite. VCF can be deployed on-premises, or as VMware Cloud via a VMware Cloud Provider.

For questions on this document, please reach out to Vaughn Stewart.

Executive Summary 

Pure Storage can help enterprises and service providers exceed SLAs and extend the capabilities of the VCF / vSphere deployments in the following key areas:

  1. Optimize data center resources. Reduce the infrastructure spend for compute & storage and eliminate hardware-defined silos.
  2. Provide storage fabric flexibility. Investment protection by enabling VCF on fibre channel fabrics, non-disruptive migration between storageprotocols (i.e. FC & iSCSI), and a future proof architecture that supports next-gen storage protocols (i.e. NVMe-oF & vVols).
  3. Simply and scale operations. Remove the need for mass data evacuations, data re-hydrations, and data reconstructions that occur with server maintenance, hardware expansions and refresh and server failures.
  4. Automate and protect the infrastructure. Increase the availability, scale, performance and business continuity of a a VCF deployment through robust integrations.

Pure has achieved a Satmetrix certified NPS score of 86.6 (top 1% of B2B CSAT) and has been identified as a leader in Gartner’s Magic Quadrant for Solid State Array for 5 years. Collectively these data points help communicate why Pure Storage FlashArray and VMware integrations provide the ideal foundation for extending the capabilities of VCF deployments.

VCF Storage Options

VCF deployments introduce the concept of domains; this is the physical assignment of hardware to support a set of virtualized applications and workloads.

•       The Management domain. This supports all VMware management tools including SDDC Manager VM, a vCenter VM for each workload domain, NSX VMs, vROPs VMs, vRNI VMs, HCX Manager VMs, etc. As of VCF 4.0 the management cluster must reside on vSAN.

•       Workload Domains. These support VMs and containers and may reside on either vSAN or 3rd party storage (which must be supported by vSphere). Workload domain storage types are classified as either Principal or Secondary. Both provide identical management capabilities within SDDC Manager; however, the former can be provisioned within SDDC Mgr and later must be manual provisioned and imported into SDDC Mgr. VMware has a roadmap for promoting protocols from secondary to principal so this document may be out of date when it comes to this classification.

This document is explicitly focused on presenting the capabilities of an on-prem VCF deployment based on vSphere 6.7 and VCF 3.9 with a FlashArray running Purity OE 5.3 and vSAN 6.7.

The data referenced in the following pages was sourced from the following sources:

https://storagehub.vmware.com/export...nical-overview

https://docs.vmware.com/en/VMware-vS...otingguide.pdf https://docs.vmware.com/en/VMware-vS...ment-guide.pdf

https://docs.vmware.com/en/VMware-vS...tion-guide.pdf

https://kb.vmware.com/s/article/2108740

https://storagehub.vmware.com/t/vsan-space-efficiency-technologies/storage-efficiency-use-case-examples-1/

https://blogs.vmware.com/virtualbloc...ntenance-mode/

https://docs.vmware.com/en/VMware-vS...37E61ECE4.html

https://docs.vmware.com/en/VMware-vS...76E46B35F.html

VMware is a strategic partner of Pure Storage. This document is intended solely for educational purposes and not for competitive use.

Core VMware vSphere Functionality

The following list covers core VMware capabilities when vSphere is deployed with vSAN and Pure Storage.

Feature vSAN FlashArray
Support DRS Yes Yes
Support RBAC Yes Yes
Support vMotion Yes Yes
Support Storage vMotion Yes Yes
Support vSphere Replication Yes

Yes

Support Thick VMDKs Yes Yes
Support EZ-Thick VMDKs Yes Yes
Support Thin VMDKs Yes Yes (recommended)
Space Reclamation of data deleted with in VMDKs Yes Yes (vVols and VMFS)
Space Reclamation for datastores No Yes
Support vRealize Automation Yes Yes
Support vRealize Orchestrator Yes Yes
Support vRealize Log Insight Yes Yes
Support vRealize Operations Manager Yes Yes
Support VMware PowerCLI Yes Yes
Support vSphere Update Manager Yes Yes
Supported by SDDC Manager Yes Yes

Supports VCF management domain

Yes

No

Supports VCF workload domains

Yes

Yes

Support datastore provisioning in SDDC Manager

Yes

Yes (with principal storage. Secondary storage provisioned in vCenter and imported) 

Support non-disruptive updates of ESXi by SDDC Manager and Update Manager 

Yes

Yes (without any data evacuation or loss of data protection)

Supports migrating ESXi nodes between workload domains

Yes (data rebalancing required in source and destination domains)

Yes (without data rebalancing)

Increase infrastructure availability and SLAs

Availability is a fundamental component within an infrastructure. The FlashArray global install base has achieved greater than six-nine’s of availability, which includes planned and unplanned downtime. In addition the FlashArray delivers 100% performance, through failure and maintenance, with non-disruptive updates delivered via Pure1. The following list covers the core tenant of availability when vSphere is deployed with vSAN and Pure Storage.

Feature

vSAN

FlashArray

Support Basic VMs

Yes

Yes

Support VMs with FT

Yes

Yes

Support VMs with MSCS

Yes (requires iSCSI LUNs mapped to guest initiators)

Yes (natively)

Disaster Recovery with SRM

Yes (requires vSphere replication infrastructure)

Yes (via native array replication)

VM Granular Snapshots

Yes (for ephemeral purposes)

Yes

VM snapshots with zero performance impact

No

Yes

Datastore Snapshots

No

Yes

Support vSphere HA

Yes

Yes

Support vMSC HA

Yes

Yes (via ActiveCluster)

Instant deployment of VMs from a template

No (VSAN requires persistent VMs to be copied from a template)

Yes (via VAAI XCopy)

Support Data at Rest Encryption AES-256

Yes (note impacts performance)

Yes

Secure erasure of customer data

No

Yes

Automatic Noisy Neighbor QoS

No

Yes

IOPs Limiting QoS

Yes

Yes

Bandwidth Limiting QoS

No

Yes

100% I/O performance thru storage failures and maintenance

No

Yes

Achieved 99.9999+% uptime across entire install base

No

Yes

Non-disruptive Software Updates Delivered via the Cloud

No

Yes

Non-disruptive upgrade (to VMs) of ESXi hosts via VMware SDDC Manager

Yes

Yes
(Datastore, VVol, RDM and In-Guest)

Predictive Support Analytics

No

Yes

Company NPS Score

39

86.6 (top 1%)

Provides sub-millisecond latency, with erasure coding, FFT=2 data protection, data encryption and data reduction enabled

No

Yes

Simplify Operations at Scale

The benefits of Pure Storage are most obvious in the area of simplified operations at scale. The FlashArray is designed to be successfully operated by any member of the IT staff – be they a member of the VMware or a storage team. This unique benefit is achieved in part by the architecture and by removing storage configuration options and associated trade-offs found in storage arrays and hyper-converged platforms. With FlashArray, all data is automatically protected with N+2 erasure coding, is encrypted with AES-256 encryption, includes automatic noisy neighbor QoS, is deduplicated and compressed for cost savings while delivering consistent sub-millisecond latency through normal operations, failures and maintenance. This allows the FlashArray to simultaneously meet the requirements of performance-centric and cost-sensitive workloads, without any configuration requirements or the need for separate deployment silos. The only storage configuration options requiring administrative effort is configuring data protection policies, bandwidth and /or IOPs limiting QoS policies, naming and sizing volumes, and connecting storage to hosts –the latter can be automated via either the Pure vCenter plug-in, vRO or vRA.

Feature

VSAN

FlashArray

Manage Storage 100% within vSphere Web Client

Yes

Yes (via plug-in)

Number of Options to Configure & Deploy a Datastore

12 Options

-        Auto Claim Storage

-        Data Reduction

-        Support Reduced Redundancy

-        Set Fault Domain

-        Number of Stripes

-        Cache Reservation

-        Number of Failures to Tolerate

-        Failure Balance Method

-        IOP limits

-        Disable Checksums

-        Force Provisioning

-        Space Reservation

2 Required Options

-        Datastore Name

-        Datastore Capacity

-        Optional: Data Protection Policies

o   Local Snap Schedule

o   Replication Schedule

Number of Options to Configure & Deploy VVols

N/A

2 Options

-        Register VASA Provider

-        Create VVol Datastore

Grow a Datastore

Yes (add new ESXi host or add disks to existing hosts)

Yes

Automate Datastore Capacity Increases

Yes (add new ESXi host or add disks to existing hosts)

Yes (via vRO)

Shrink a Datastore

Yes (eject ESXi host or disks)

No (VMFS cannot shrink but all datastores are thin provisioned and only consume capacity of data stored)

Support Multiple Datastores

No

Yes

Automatic Data Reduction

No

Yes

Automatic FTT=2 Data Protection

No

Yes

Automatic Data at Rest Encryption

No

Yes

Complete vSphere Update Manager without reducing Data Protection or Migrating data

No

Yes

Complete Storage SW/FW Upgrade / Update w/o Reducing Data Protection

No

Yes

Complete Storage SW/FW Upgrade / Update w/o Reducing I/O Performance

No

Yes

Provides REST API Interface

Yes

Yes

Supports PowerCLI

Yes

Yes

Zero configuration required to increase storage performance

No (change policy and rewrite data or create new cluster and migrate data)

Yes (non-disruptive, in place controller upgrade)

Zero configuration required to increase storage capacity

No

Yes (insert a data pack)

Zero Performance impacting snapshots and replication

No

Yes

Data can be cloned for access by Physical Servers and other hypervisors

No

Yes

Reduce TCO via Storage Efficiency

Pure Storage is widely recognized as offering the most robust set of data reduction technologies in the industry, commonly delivering 3X to 4X greater data reduction and up to 8X greater total storage efficiency than HCI platforms. Efficiency spans beyond data reduction to include UNMAP and storage architecture overheads like data protection (RAID), caches, failover and slack space capacity reservations. At the end of the day storage efficiency directly translates into cost savings be it in measured in terms of virtual machines (VMs) per rack unit (RU), TBs per RU, GBs per dollar.

Feature

VSAN

FlashArray

Additional hypervisor node required to add capacity

Yes

No

All Inclusive Storage Software?

No (vSphere Replication is extra)

Yes

Native Replication

No

Yes

10% Storage Capacity Required for Cache?

Yes

No

30% Storage Capacity Required for Slack Space?

Yes (Cluster wide data rebalancing when any host hits 80% utilization)

No

Storage Capacity Required for Host Failures?

Yes (percentage is calculated as N/N-FTT)

No

RAID Overhead

33% (FTT=2 Erasure Coding)
50% (FTT=1 Mirror)
67% (FTT=2 Mirror)

~12.5% (RAID-HA)

Global Data Reduction

No (per host disk group)

Yes

Data Deduplication

Yes (optional due to performance impact)

Yes (always on)

Deduplication Granularity

4 KB

512 Bytes

Inline Data Compression

Yes (optional due to performance impact)

Yes (always on)

Multi-Algorithm, Background Compression

No

Yes (always on)

Zero Removal

No

Yes (always on)

Pattern Removal

No

Yes (always on)

VMDK UNMAP / TRIM

Yes

Yes

Datastore UNMAP / TRIM

No

Yes (automated via vRO)

Reduce TCO via Server Efficiency

Expanding beyond storage efficiency, one needs to consider the cost placed on server CPU and memory resources when deploying VMs on a hyper-converged platform like vSAN. The benefit of the FlashArray can be measured in terms of an increase in VMs per hypervisor node. This results in fewer servers and software licenses; greater VMs per RU, VMs for Rack/floor tile, and VMs per network switch port.

Feature

VSAN

FlashArray

ESXi CPU and Memory Overhead for Storage IO

Yes (estimated ~5-10%)

Yes (estimated ~1%)

ESXi CPU and Memory Overhead due to I/O Latency

Yes (estimated ~5-10%)

Yes (estimated ~1%)

Software License Required for Storage

No (VCF bundle)

No

Replication Software License Required

Yes (vSphere Replication
or 3rd party)

No

ESXi CPU and Memory Overhead for Data Replication

Yes (estimated ~5-10%)

No

ESXi CPU and Memory Overhead for Data Encryption

Yes (estimated ~5-10%)

No

Networking Details

 

Feature

VSAN

FlashArray

Support FC (4/8/16 Gb)

No

Yes

Support 10GbE

Yes

Yes

Support 40GbE

Yes

Yes

Support iSCSI LUNs

Yes (In-Guest initiator)

Yes (Datastore, VVol, RDM and In-Guest initiator)

I/O Amplification (Increased Network & Disk Load)

Yes (4.5X for FTT=2 with Erasure Coding)

No

Support Jumbo Frames

Yes

Yes

Recommend or Require Jumbo Frames

No

No

 

Security Certification Details

 

Feature

VSAN

FlashArray

Support Data at Rest Encryption AES-256

Yes (via vSAN encryption)

Yes

FIPS 140-2 certification

Yes

Yes

AES validation (FIPS 197 and SP 800-38A)

No

Yes

DRBG validation (SP 800-90A)

No

Yes

HMAC validation (FIPS 198-1)

No

Yes

SHA validation (180-4)

No

Yes

NIAP Certification

 

Yes

Yes

Common Criteria Compliant

Yes

Yes