VMware Virtual SAN Technical Best Practices

Cormac Hogan, VMware

Kiran Madnani, VMware

STO5027

#STO5027

2

Agenda

VMware’s vision for SDS

What is Virtual SAN?

Key Components

Hardware considerations

Use Cases

Managing VSAN

Demo

Beta Information!

3

Software-Defined Data Center

Software-Defined Storage

SDDC | SDS

All infrastructure is virtualized

and delivered as a service, and

the control of this data center is

entirely automated by software.

Heterogeneous storage resources

are abstracted into logical pools,

consumed and managed through

app-centric policy-based

automation

4

VMware Approach to Software-Defined Storage

Software-Defined Storage

Virtualized Data Plane

Shared

Storage

VM-centric Data Services

Policy-Driven Control Plane

HDD SSD

Server Direct

Attached

Extensible framework

for ecosystem of VM-

centric data services.

Common

management model

based on VM-level

policies

Hypervisor-based

pooling of

heterogeneous

storage resources

5 VMworld 2013

What is Virtual SAN?

6 VMworld 2013

Introducing Virtual SAN (VSAN)

vSphere

VSAN

Hard disks Hard disks SSD SSD Hard disks

SSD

…

VSAN Datastore

Product Overview

• Scale out Storage built into the hypervisor

• Clusters ESX host attached storage

• Flash-optimized converged compute + storage

solution

• Software solution - Uses industry standard

components

• vSphere integrated management

7 VMworld 2013

Introducing Virtual SAN (VSAN)

vSphere

VSAN

Hard disks Hard disks SSD SSD Hard disks

SSD

…

VSAN Datastore

Features

• Dynamic and capacity performance scaling

• Shared storage properties

• High Performance – Flash based read & write

cache

• High Resiliency – Distributed RAID; No single

points of failure

• VM-Centric management

• Automated SLA management

8 VMworld 2013

VSAN Value and Differentiation

Native to ESX hypervisor -

improves resource efficiency &

latency

Storage platform architected for

VM-level data operations and

management

Built from ground up using Policy-

Driven Management principles

vSphere integrated management

Radically Simple Storage built for

the virtualization admin

Radically Simple Enterprise Storage

Significantly lower TCO without compromising performance

vSphere

VSAN

Hard disks Hard disks SSD SSD Hard disks

SSD

…

VSAN Datastore

9 VMworld 2013

Key Components

10

Requirements

At least 3 x ESXi hosts running version 5.5

1 x vCenter server running version 5.5; managed thru web-client

Each host containing at least 1 unused SSD & 1 unused HDD

1Gb or 10Gb network between hosts

VMworld 2013

11 VMworld 2013

Hardware Considerations

12 VMworld 2013

VSAN Hardware Requirements

SAS/SATA Controller or RAID

Controller must work in

passthru/JBOD/HBA mode

SAS/SATA/PCIe SSD

SAS/SATA HDD

1Gb/10Gb NIC

Server on

vSphere HCL

13

Best Practices: Hardware Selection Considerations

Network

• VSAN supports both 1Gb & 10Gb NICs

• VSAN supports both VSS & VDS

Storage Controller

• HBA or RAID controller with JBOD mode for optimal performance

Solid State Disk

• Pick SSD’s based on performance and reliability

• Best practice: ~10% of storage should be SSD

HDD’s

• 7.2K for capacity or 10K for performance

VMworld 2013

14 VMworld 2013

Use Cases

15 VMworld 2013

VMware Virtual SAN – Initial Use Cases

• Handle peak performance such as boot, login, read/write storms

• Seamless granular scaling without huge upfront investments

• Support high VDI density

• Rapid storage provisioning and complete automation

• Ideal price/performance

• Minimizes data center footprint

• Integrated with vSphere Replication and VMware SRM

• Reduces cost of storage

• Minimizes data center footprint

Virtual Desktop (VDI)

Tier 2 / Tier 3

Test and Dev

Private Cloud

DR

Target

Site A Site B

16 VMworld 2013

Managing VSAN

17

VSAN Workflow – Configure & Deploy

Configure

VSAN

Determine VM

Storage

Requirements

Create VM

Storage Policy

using capabilities

Start VM

Deployment

Choose VM

Storage

Policy

Verify VSAN

met

requirements

Repeat as

necessary GO

Stop

VMworld 2013

You are

here

Finish VM

Deployment

VSAN

Capabilities

surfaced

18

Configure VSAN

•VSAN is configured in just a few clicks.

Setup

VSAN

Network

Enable

VSAN

on the Cluster

Select

Manual

or Automatic

•Automatic mode: all empty local disks are claimed by VSAN for the

creation of the vsanDatastore

•Manual mode: the administrator must manually select empty local disks

to add the the vsanDatastore.

If Manual,

pick

Disks/SSDs

VMworld 2013

19

VSAN Fully Integrated with vSphere

•All the management tasks pertaining to the installation, configuration &

monitoring of VSAN will be done from the vSphere Web Client.

VMworld 2013

20

vsanDatastore

A single vsanDatastore is created, using storage from multiple hosts and

multiple disks in the cluster.

Hard disks Hard disks SSD SSD Hard disks SSD

vSphere

VSAN

VSAN Datastore

VMworld 2013

…

21

vsanDatastore for Availability

The virtual machine is comprised of storage objects (VM Home, VMDK,

delta, swap) which may be distributed across the hosts and disks in the

VSAN cluster.

VMs may have a replica copy for availability, or stripe for HDD performance

Hard disks Hard disks SSD SSD Hard disks SSD

Replica & Stripes for VM 1

Replica & Stripes for VM 2

vSphere

VSAN

…

VMworld 2013

22

VSAN Scale-Out Storage – Radically Simple

vSphere

VSAN

Hard disks Hard disks SSD SSD Hard disks

SSD

VSAN Aggregated Datastore

Hard disks SSD

Hard disks SSD

vSphere

VSAN

VSAN Aggregated Datastore

vSphere

VSAN

VSAN Aggregated Datastore

vSphere

VSAN

VMworld 2013

23

Best Practices: Scale Out

All hosts in a VSAN cluster be similarly or identically configured

It avoids a single host having a majority of running VMs.

It avoids a single host having a majority of VM storage components.

VMware recommends deploying a

balanced cluster, both from a compute

and storage perspective

VMworld 2013

24

VSAN Workflow – Configure & Deploy

Configure

VSAN

Determine VM

Storage

Requirements

Create VM

Storage Policy

using

capabilities

Start VM

Deployment

Choose VM

Storage

Policy

Verify VSAN

met

requirements

Repeat as

necessary GO

Stop

VMworld 2013

Finish VM

Deployment

VSAN

Capabilities

surfaced

You are

here

25

What are the key components of Virtual SAN?

VMworld 2013

vSphere

VSAN

Hard disks Hard disks SSD SSD Hard disks

SSD

…

VSAN Datastore

Capacity,

Availability, Performance

VM Storage Policy

Reflect the storage

requirements of the

application

Based on VSAN

datastore

capabilities

Picked during VM

deployment

Allows VM

deployment at

scale

26 VMworld 2013

Which Capabilities does VSAN support?

• Number of disk stripes per object

The number of HDD's across which each replica of a VMDK object is distributed.

• Number of failures to tolerate

Defines the number of hosts, network and/or disk failures a VMDK can tolerate.

• Object space reservation

% of the logical size of VMDK, including snapshots, that should be reserved (thick

provisioned). Rest of object is thin.

• Flash read cache reservation

Flash capacity reserved as read cache for the storage object. Specified as a percentage of

the VMDK capacity.

• Force provisioning

If enabled, object will be provisioned even if the policy requirements cannot be satisfied by

the vsanDatastore.

27

Storage Capabilities used in policies

Capability Use Case Value

1 Number of failures to tolerate

(RAID 1 – Mirror) Redundancy

Default 1

Max 3

2 Number of disk stripes per object

(RAID 0 – Stripe) Performance

Default 1

Max 12

3 Object space reservation Thick Provisioning Default 0

Max 100%

4 Flash read cache reservation Performance Default 0

Max 100%

5 Force provisioning Override policy Disabled

VMworld 2013

28

VSAN Workflow – Configure & Deploy

Configure

VSAN

Determine VM

Storage

Requirements

Create VM

Storage Policy

using

capabilities

Start VM

Deployment

Choose VM

Storage

Policy

Verify VSAN

met

requirements

Repeat as

necessary GO

Stop

VMworld 2013

Finish VM

Deployment

VSAN

Capabilities

surfaced

You are

here

29

Decisions when creating a VM Storage Policy

Do I want availability for this VM?

• Number of failures to tolerate should be a capability in the policy.

Do I want additional performance (above the default) for this VM?

• Number of disk stripes and Flash read cache reservation are capabilities that

can be used for performance purpose.

Do I want the VM to be thickly provisioned?

• Object space reservation should be a capability in the policy.

Do I want the VM deployed even if VSAN cannot meet the policy?

• Force provisioning should be a capability in the policy.

VMworld 2013

30

VSAN Policy definition

31

Best Practices: VM Storage Policy

Number of Disk Stripes per object

should be left at 1, unless the the IOPs requirement of the VM is not being met

by the SSD cache.

Flash Read Cache Reservation

should be left at 0, unless there is a specific performance requirement to be

met by the VM.

Proportional Capacity

should be left at 0, unless thick provisioning of virtual machines is required.

Force Provisioning

Should be left disabled, unless the VM needs to be provisioned, even if not in

compliance

VMworld 2013

32

VSAN Workflow – Configure & Deploy

Configure

VSAN

Determine VM

Storage

Requirements

Create VM

Storage Policy

using

capabilities

Start VM

Deployment

Choose VM

Storage

Policy

Verify VSAN

met

requirements

Repeat as

necessary GO

Stop

VMworld 2013

Finish VM

Deployment

VSAN

Capabilities

surfaced

You are

here

33

VM Provisioning Example (1 of 2)

During VM provisioning, an appropriate pre-configured VM Storage Policy

is selected for the VM.

If the vsanDatastore understands the capabilities in the VM Storage

Policy, it will be displayed as a matching resource.

VMworld 2013

34

VM Provisioning Example (2 of 2)

If the vsanDatastore can

satisfy the VM Storage

Policy, the the VM Summary

tab will display the VM as

compliant.

If not, due to failures, or the

force provisioning capability,

the VM will be shown as

non-compliant.

VMworld 2013

35

Visualizing the layout

VMworld 2013

Support for mapping the

layout to visualize:

Physical-to-virtual mapping

Virtual-to-physical mapping

36

IO workflow

All VM I/O is directed to the SSD. Writes are later destaged to HDD.

If the requested read block is not in cache, the request is directed to HDD

Hard disks SSD

vSphere

VSAN

VSAN Datastore

1

2

Write

Hard disks SSD

vSphere

VSAN

VSAN Datastore

1 2 Read

VMworld 2013

37

VM requirements changed?

Traditional Approach

1. Migrate VMs from datastore

2. Decommission LUN/Volume

3. Create new LUN/Volume with the

new storage requirements

4. Format of the LUN with VMFS in

the case of block storage

5. Migrate VMs to new datastore.

VSAN

1. Edit the VM Storage Policy

2. Apply the changed policy

vs.

38

Maintenance Mode – planned downtime

VMworld 2013

3 Maintenance mode

options:

Ensure accessibility

Full data migration

No data migration

39

Managing Failures - unplanned downtime

VMworld 2013

Through policies, VM’s on

VSAN can tolerate multiple

failures

Disk Failure

SSD Failure

Network Failure

Server Failure

VM’s continue to run

Parallel rebuilds minimize

performance pain

40

Observing performance

VMworld 2013

4 ways to monitor

performance:

esxtop

Performance Manager UI

RVC & Observer

41 VMworld 2013

Demo

42

Demo Time

This next section of the presentation will look at:

1. Ease of Setup

2. Building a VM Storage Policy

3. Change that VM Storage Policy as VM I/O requirements change

4. Highly Available Virtual Machines

5. VSAN & vSphere HA Interoperability

VMworld 2013

43

Demo - Key Takeaways #1

• Network connection required for communication and I/O purposes.

• Setup is very simple.

• Scaling out storage and compute in a VSAN cluster is as simple as adding a new host to the cluster.

• Policies enable Software Driven Storage.

• As VM storage requirements change, administrators can simply update the policy.

Compare this to a physical SAN or NAS infrastructure where new datastores would need provisioning to satisfy changing VM I/O requirements.

• VMs can be migrated between a vsanDatastore, traditional VMFS and NFS datastores.

VMworld 2013

44

Demo - Key Takeaways #2

• VSAN & vSphere HA provides high availability at both the storage AND compute layers.

More detail on VSAN & HA interoperability can be found in session BCO5047 –

vSphere HA – What’s New and Best Practices by Keith Farkas & Jeff Hunter

VMworld 2013

45 VMworld 2013

VSAN Beta Information

46

• It’s free

• It’s as easy as installing vSphere

• It gives you the chance to win an iPad!

Register for Virtual SAN Beta Now!

47 47

Other VMware Activities Related to This Session

HOL:

HOL-SDC-1308

Virtual Storage Solutions

Group Discussions:

STO1001-GD

VSAN with Cormac Hogan and VMware R&D Engineers

THANK YOU

VMware Virtual SAN Technical Best Practices

Cormac Hogan, VMware

Kiran Madnani, VMware

STO5027

#STO5027