planning a successful private cloud - cloudstack collaboration europe 2013

Tim Mackey – XenServer Community Evangelist

Planning your private cloudLearning from the lessons of others

CloudStack Collaboration Conference Europe 2013

© Citrix 2013. More information at xenserver.org and follow me on twitter @XenServerArmy

Private Cloud, Why Now?

• Valid alternative to public clouds that are cheap and readily available

• Speed and agility of deployment

• Control of corporate assets

• Cloud Management Platform market maturity

• Future-proofing for nextgen, webscale workloads

“An IaaS cloud is a highly automated

virtual infrastructure that enables self-service resource

requests, and consumption of the shared environment is tracked for either

chargeback or showback purposes.”

Forrester Research

100’s of pilots and few production deployments in 2011; expected to be 10 times more in 2012 - Gartner


Enterprise Objectives for Cloud

Remove IT as a service delivery critical pathSelf ServiceSelf Service

Reduce IT operational costsManagement Automation

Management Automation

Consistent application and service deploymentWorkload Standardization

Workload Standardization

Manage complete infrastructure, regardless of scaleCentralized ManagementCentralized

Management

Drive reduced capital requirementsSmarter VirtualizationSmarter VirtualizationCa

pita

l Lev

era

geW

ork

forc

e L

eve

rage

Visibility into user and line of business usageUsage MeteringUsage Metering


Traditional Data Center Amazon-style Cloud

AvailabilityZone

AvailabilityZone

Object Storage

vCenter

vSphere

ESXiCluster

Enterprise Networking (e.g., VLAN)

Enterprise Storage (e.g., SAN)

ESXiCluster

ESXiCluster

CloudStack Management ServerLegacy Availability Zone

AvailabilityZone

ORAND

Best practices aren’t always

Density in the cloud


Traditional Server Virtualization

• Core Objectivesᵒ Server consolidationᵒ Power and cooling savingsᵒ Hardware independence

• Looks Likeᵒ VM Density < 20 ᵒ vCPU = pCPUᵒ vRAM = pRAMᵒ Low IOPSᵒ Redundancy mattersᵒ No templates

7


Desktop Virtualization

• Core Objectivesᵒ Control of IPᵒ Ensuring patch complianceᵒ Supporting mobile workstyles

• Looks Likeᵒ 50 -100 VMs per hostᵒ 2-4 vCores = pCoreᵒ 1-2 vRAM = pRAMᵒ High IOPSᵒ Boot stormsᵒ Network contentionᵒ Highly templated

8


Cloud Services

• Core Objectivesᵒ Agile provisioningᵒ High degrees of tenant isolationᵒ Low operating margins

• Looks Likeᵒ 50-250 VMs per hostᵒ 2-8 vCore = pCoreᵒ vRAM = pRAMᵒ Moderate IOPSᵒ Network contentionᵒ Largely templated

9

Planning the network


Before Virtualization

• Simple management model

• Provisioning took a long time

• Topologies fairly static


Along Comes Server Virtualization

• Multiple VMs/hostᵒ Loss of visibilityᵒ Loss of control

• Edge moves into hostᵒ Network admins need to understand

server virtualization


Example 1 – Mirroring Traffic

• Without virtualization this is pretty easy

• With virtualization you now have multiple VMs


Example 1 – Mirroring Traffic

• Without virtualization this is pretty easy

• With virtualization you now have multiple VMsᵒ Plus VMs can move

• Better to monitor at virtual switch


Example 2 – Network Policies

• Server admins have significant impact on the networkᵒ IP and MAC Addressᵒ Virtual NICsᵒ Protocols and ports

• Granular network control requires awareness of virtual machinesᵒ Define policies at virtual switch


Network Management Tools Lag

• Assumptions of fixed topologyᵒ Fine for physicalᵒ Challenge for dynamic environment

• Not virtualization awareᵒ Incorrect topologyᵒ Incomplete topologyᵒ VM actions obsolete data

X


Virtual Machine Density Planning

• Host capacities are growing rapidlyᵒ vSphere 5 > 512 VMsᵒ RHEV 3 > 1000 VMsᵒ Hyper-V > 2048 VMs

• Clouds and VDI push limits

• Top of rack switch selection matters?ᵒ ARP tableᵒ Switching performance dropsᵒ VM starts, but can’t connect

VMVM

VMVMVM

VMVM

VMVMVM

Host 1

Host 2

VMVM

VMVMVM

VMVM

VMVM

Storage choice is critical


Shared storage growth and provisioning time

1,000

500

VMs

Cost, AU100 200

500

VMs

Provisioning efficiency

AU – arbitrary units


Combined efficiency and storage evolution

Redesign

1,000

500

VMs

100 200 Cost, AU

VMs

1,000

500

Cost, AU100 200

?Alternatives



Redesign

Efficiency and pod storage

1,000

500

VMs

100 200 Cost, AU

POD #1

POD #2

POD #31,000

500

VMs

100 200 Cost, AU


No redesign


What about local storage?

1,000

500

VMs

Cost, AU 100 200

50

VMs

Provisioning efficiency



PODtrend

Traditionaltrend

Cost-Performance Trends

Shared Storage Local Storage

1,000

500

VMs

Cost, AU100 200

1,000

500

VMs

100 200 Cost, AU

Local storage

Performancetrend

Local storagetrend


Understanding disk usage and sizing

VM_COUNT * VM_DISK + SWAP = TOTAL_DISK

VM_COUNT * (OS_PARTITION + USR_DATA) + SWAP = TOTAL_DISK

VM_COUNT = (TOTAL_DISK – SWAP) ÷ (OS_PARTITION + USR_DATA)

VM_DISK SWAPUSR_DATAOS_PARTITION

TOTAL_DISK


Templates and thin provisioning matter

VM_COUNT * USR_DATA + OS_PARTITION + SWAP = TOTAL_DISK

VM_COUNT = (TOTAL_DISK – SWAP – OS_PARTITION) ÷ USR_DATA

SWAP

TOTAL_DISK

OS_PARTITIONUSR_DATA


Storage performance

IO per Disk

RAID PENALTY

0 1

1 2

5 4

6 6

10 2

50 4

Write Penalties

RPM IOPS

SSD 5,000+

SAS 15,000 175

SAS 10,000 125

SAS 7,200 75

VM Utilization

ITEM ~VALUE

IOPS per VM 20

Size, KB 4-8

Writes, % 80

Reads, % 20

IOPS = [IOPS per DISK]*[Disk Count]*([% of Reads]+[% of Writes] ÷ [RAID Write Penalty])

VM_COUNT = IOPS ÷ [IOPS per VM]

Blueprint for success ….


Cloud Builder Lessons from Zynga

• Public clouds are minivans

• zCloud is a race carᵒ zCloud is optimized for social gamingᵒ Know your application requirements

• Don’t rent what you can own cheaperᵒ Cloud operator doesn’t care about your successᵒ Optimized applications might be key

• Ensure you have backup plansᵒ Usage can and does spikeᵒ Outages can and do happen

vs.


Cloud Builder Lessons From Telcos

• Utility computing fits business modelᵒ Traditionally operate a low margin business modelᵒ Understand tiered service offeringsᵒ Have a history with instant provisioning

• Tiered service demands infrastructure flexibilityᵒ “Cost per instance” is paramountᵒ Charge extra for premium featuresᵒ Instance doesn’t imply virtualizationᵒ Be prepared to change vendors if better model appears

• Provisioning agility expectedᵒ Customers expect instant self service access and detailed billing


Service Offerings

• Clearly define what you want to offerᵒ What types of applicationsᵒ Who has access, and who owns themᵒ What type of access

• Define how templates need to be managedᵒ Operating system supportᵒ Patching requirements

• Define expectations around compliance and availabilityᵒ Who owns backup and monitoring


Define Tenancy Requirements

• Department data local to departmentᵒ Where is the application data stored

• Data and service isolationᵒ VM migration and host HAᵒ Network services

• Encryption of PII/PCIᵒ Where do keys live when data location unknownᵒ Need encryption designed for the cloud

• Showback to stakeholdersᵒ More than just usage, compliance and audits


Virtualization Infrastructure

• Hypervisor defined by service offeringsᵒ Don’t select hypervisor based on “standards”ᵒ Understand true costs of virtualizationᵒ Multiple hypervisors are “OK”ᵒ Bare metal can be a hypervisor

• To “Pool” resources or notᵒ Is there a real requirement for pooled resourcesᵒ Can the cloud management solution do better?ᵒ Real cost of shared storage

• Primary storage defined by hypervisor

• Template storage defined by solutionᵒ Typically low cost options like NFS


Cloud Operations

• Design for maintainability

• Monitor critical componentsᵒ Management servers and system support VMsᵒ Hypervisor hosts, and critical infrastructureᵒ End user deployment environments

If your cloud has maintenance windows, you’re doing it wrong.- Allan Leinwand Former CTO Zynga

Work better. Live better.

planning a successful private cloud - cloudstack collaboration europe 2013

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