This document provides an overview of VMware Virtual SAN (VSAN) technical best practices. It discusses VSAN's key components, hardware considerations, use cases, management, and demo. VSAN is a software-defined storage solution that clusters direct-attached host storage and provides a virtual SAN datastore. It has integrated management with vSphere and uses capabilities and policies to enable VM-centric storage provisioning and automation. The document demonstrates how to configure VSAN, create VM storage policies, and deploy VMs according to policies and capabilities.

1. VMware Virtual SAN Technical Best Practices
Cormac Hogan, VMware
Kiran Madnani, VMware
STO5027
#STO5027

2. 2
Agenda
 VMware’s vision for SDS
 What is Virtual SAN?
 Key Components
 Hardware considerations
 Use Cases
 Managing VSAN
 Demo
 Beta Information!

3. 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. 4
VMware Approach to Software-Defined Storage
Software-Defined Storage
Virtualized Data Plane
Shared
Storage
VM-centric Data Services
Policy-Driven Control Plane
HDDSSD
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. 5 VMworld 2013
What is Virtual SAN?

6. 6 VMworld 2013
Introducing Virtual SAN (VSAN)
vSphere
VSAN
Hard disksHard 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. 7 VMworld 2013
Introducing Virtual SAN (VSAN)
vSphere
VSAN
Hard disksHard 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. 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 disksHard disks
SSD SSD Hard disks
SSD
…
VSAN Datastore

9. 9 VMworld 2013
Key Components

10. 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. 11 VMworld 2013
Hardware Considerations

12. 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. 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. 14 VMworld 2013
Use Cases

15. 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. 16 VMworld 2013
Managing VSAN

17. 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. 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. 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. 20
vsanDatastore
A single vsanDatastore is created, using storage from multiple hosts and
multiple disks in the cluster.
Hard disksHard disksSSD SSD Hard disksSSD
vSphere
VSAN
VSAN Datastore
VMworld 2013
…

21. 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 disksHard disksSSD SSD Hard disksSSD
Replica & Stripes for VM 1
Replica & Stripes for VM 2
vSphere
VSAN
…
VMworld 2013

22. 22
VSAN Scale-Out Storage – Radically Simple
vSphere
VSAN
Hard disksHard 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. 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. 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. 25
What are the key components of Virtual SAN?
VMworld 2013
vSphere
VSAN
Hard disksHard 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. 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. 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. 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. 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. 30
VSAN Policy definition

31. 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. 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. 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. 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. 35
Visualizing the layout
VMworld 2013
Support for mapping the
layout to visualize:
 Physical-to-virtual mapping
 Virtual-to-physical mapping

36. 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 disksSSD
vSphere
VSAN
VSAN Datastore
1
2
Write
Hard disksSSD
vSphere
VSAN
VSAN Datastore
1 2
Read
VMworld 2013

37. 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. 38
Maintenance Mode – planned downtime
VMworld 2013
3 Maintenance mode
options:
 Ensure accessibility
 Full data migration
 No data migration

39. 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. 40
Observing performance
VMworld 2013
 4 ways to monitor
performance:
 esxtop
 Performance Manager UI
 RVC & Observer

41. 41 VMworld 2013
Demo

42. 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. 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. 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. 45 VMworld 2013
VSAN Beta Information

46. 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. 4747
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

48. THANK YOU

50. VMware Virtual SAN Technical Best Practices
Cormac Hogan, VMware
Kiran Madnani, VMware
STO5027
#STO5027