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Essential Virtual SAN (VSAN): Administrator's Guide to VMware Virtual SAN

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Essential Virtual SAN (VSAN): Administrator's Guide to VMware Virtual SAN


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  • The first book on VMware Virtual SAN -- from two of VMware's "superstar" experts, Cormac Hogan and Duncan Epping
  • How Virtual SAN works, and what it offers
  • How to architect Virtual SAN environments for maximum value
  • How to avoid potential "gotchas" and troubleshoot problems


  • Copyright 2015
  • Edition: 1st
  • Book
  • ISBN-10: 0-13-385499-X
  • ISBN-13: 978-0-13-385499-2

Understand and implement VMware Virtual SAN: the heart of tomorrow’s Software-Defined Datacenter (SDDC)

VMware’s breakthrough Software-Defined Datacenter (SDDC) initiative can help you virtualize your entire datacenter: compute, storage, networks, and associated services. Central to SDDC is VMware Virtual SAN (VSAN): a fully distributed storage architecture seamlessly integrated into the hypervisor and capable of scaling to meet any enterprise storage requirement.

Now, the leaders of VMware’s wildly popular Virtual SAN previews have written the first authoritative guide to this pivotal technology. You’ll learn what Virtual SAN is, exactly what it offers, how to implement it, and how to maximize its value.

Writing for administrators, consultants, and architects, Cormac Hogan and Duncan Epping show how Virtual SAN implements both object-based storage and a policy platform that simplifies VM storage placement. You’ll learn how Virtual SAN and vSphere work together to dramatically improve resiliency, scale-out storage functionality, and control over QoS.

Both an up-to-the-minute reference and hands-on tutorial, Essential Virtual SAN uses realistic examples to demonstrate Virtual SAN’s most powerful capabilities. You’ll learn how to plan, architect, and deploy Virtual SAN successfully, avoid gotchas, and troubleshoot problems once you’re up and running.

Coverage includes

  • Understanding the key goals and concepts of Software-Defined Storage and Virtual SAN technology
  • Meeting physical and virtual requirements for safe Virtual SAN implementation
  • Installing and configuring Virtual SAN for your unique environment
  • Using Storage Policy Based Management to control availability, performance, and reliability
  • Simplifying deployment with VM Storage Policies
  • Discovering key Virtual SAN architectural details: caching I/O, VASA, witnesses, pass-through RAID, and more
  • Ensuring efficient day-to-day Virtual SAN management and maintenance
  • Interoperating with other VMware features and products
  • Designing and sizing Virtual SAN clusters
  • Troubleshooting, monitoring, and performance optimization

Sample Content

Online Sample Chapter

Administrator's Guide to VMware Virtual SAN: Introduction to VSAN

Sample Pages

Download the sample pages (includes Chapter 1 and Index)

Table of Contents

Foreword by Ben Fathi xvii

Foreword by Charles Fan xix

About the Authors xxi

About the Technical Reviewers xxiii

Acknowledgments xxv

Reader Services xxvii

Introduction xxix

Chapter 1 Introduction to VSAN 1

    Software-Defi ned Datacenter 1

    Software-Defi ned Storage 2

    Hyper-Convergence/Server SAN Solutions 3

    Introducing Virtual SAN 4

    What Is Virtual SAN? 5

    What Does VSAN Look Like to an Administrator? 8

    Summary 11

Chapter 2 VSAN Prerequisites and Requirements for Deployment 13

    VMware vSphere 5.5 13

        ESXi 5.5 U1 14

        ESXi Boot Considerations 14

    VSAN Requirements 15

        VMware Hardware Compatibility Guide 15

        VSAN Ready Nodes 15

        Storage Controllers 16

        Magnetic Disks 18

        Flash Devices 19

    Network Requirements 20

        Network Interface Cards 20

        Supported Virtual Switch Types 21

        VMkernel Network 21

        VSAN Network Traffi c 22

        Jumbo Frames 22

        NIC Teaming 23

        Network I/O Control 23

        Firewall Ports 23

    Summary 24

Chapter 3 VSAN Installation and Confi guration 25

    VSAN Networking 25

    VMkernel Network for VSAN 26

    VSAN Network Confi guration: VMware Standard Switch 27

    VSAN Network Confi guration: vSphere Distributed Switch 28

        Step 1: Create the Distributed Switch 28

        Step 2: Create a Distributed Port Group 29

        Step 3: Build VMkernel Ports 30

    Possible Network Confi guration Issues 33

    Network I/O Control Confi guration Example 35

    Design Considerations: Distributed Switch and Network I/O Control 38

        Scenario 1: Redundant 10GbE Switch Without “Link Aggregation” Capability 39

        Scenario 2: Redundant 10GbE Switch with Link Aggregation Capability 42

    Creating a VSAN Cluster 45

    The Role of Disk Groups 45

        Disk Group Maximums 46

        Why Confi gure Multiple Disk Groups in VSAN? 46

        SSD to Magnetic Disk Ratio 47

        Automatically Add Disks to VSAN Disk Groups 48

        Handling Is_local or Is_SSD Issues 48

        Manually Adding Disks to a VSAN Disk Group 50

        Disk Group Creation Example 50

        VSAN Datastore Properties 53

    Summary 53

Chapter 4 VM Storage Policies on VSAN 55

    Introducing Storage Policy-Based Management in a VSAN Environment 56

        Number of Failures to Tolerate 58

        Number of Disk Stripes Per Object 59

        Flash Read Cache Reservation 61

        Object Space Reservation 61

        Force Provisioning 61

    VASA Vendor Provider 62

        An Introduction to VASA 62

        Storage Providers 63

    VSAN Storage Providers: Highly Available 63

        Changing VM Storage Policy On-the-Fly 64

        Objects, Components, and Witnesses 68

    VM Storage Policies 68

        Enabling VM Storage Policies 69

        Creating VM Storage Policies 70

        Assigning a VM Storage Policy During VM Provisioning 70

    Summary 71

Chapter 5 Architectural Details 73

    Distributed RAID 73

    Objects and Components 74

        Component Limits 76

        Virtual Machine Storage Objects 77

        Virtual Machine Home Namespace 77

        Virtual Machine Swap 78

        VMDKs and Deltas 78

        Witnesses and Replicas 79

        Object Layout 79

    VSAN Software Components 82

        Component Management 83

        Data Paths for Objects 83

        Object Ownership 83

        Placement and Migration for Objects 84

        Cluster Monitoring, Membership, and Directory Services 85

        Host Roles (Master, Slave, Agent) 85

        Reliable Datagram Transport 86

    On-Disk Formats 86

        Flash Devices 86

        Magnetic Disks 86

    VSAN I/O Flow 87

        The Role of the SSD 87

        Anatomy of a VSAN Read 88

        Anatomy of a VSAN Write 90

        Retiring Writes to Magnetic Disks 91

        Data Locality 91

    Storage Policy-Based Management 92

    VSAN Capabilities 92

        Number of Failures to Tolerate Policy Setting 93

        Best Practice for Number of Failures to Tolerate 95

        Stripe Width Policy Setting 96

        Striping on VSAN Outside of Policy Setting 98

        Stripe Width Maximum 100

        Stripe Width Confi guration Error 101

        Stripe Width Chunk Size 102

        Stripe Width Best Practice 102

        Flash Read Cache Reservation Policy Setting 103

        Object Space Reservation Policy Setting 103

        VM Home Namespace Revisited 104

        Swap Revisited 104

        How to Examine the VM Swap Storage Object 104

        Delta Disk / Snapshot Caveat 106

        Verifying How Much Space Is Actually Consumed 106

        Force Provisioning Policy Setting 107

        Witnesses and Replicas: Failure Scenarios 107

        Recovery from Failure 110

        What About Stretching VSAN? 113

    Summary 115

Chapter 6 VM Storage Policies and Virtual Machine Provisioning 117

    Policy Setting: Number of Failures to Tolerate = 1 117

    Policy Setting: Failures to Tolerate = 1, Stripe Width = 2 124

    Policy Setting: Failures to Tolerate = 2, Stripe Width = 2 128

    Policy Setting: Failures to Tolerate = 1, Object Space Reservation = 50 Percent 132

    Policy Setting: Failures to Tolerate = 1, Object Space Reservation = 100 Percent 136

    Default Policy 138

    Summary 141

Chapter 7 Management and Maintenance 143

    Host Management 143

        Adding Hosts to the Cluster 143

        Removing Hosts from the Cluster 145

        ESXCLI VSAN Cluster Commands 145

    Maintenance Mode 146

    Recommended Maintenance Mode Option for Updates and Patching 148

    Disk Management 149

        Adding a Disk Group 149

    Removing a Disk Group 150

        Adding Disks to the Disk Group 152

        Removing Disks from the Disk Group 153

    Wiping a Disk 153

        ESXCLI VSAN Disk Commands 154

    Failure Scenarios 155

        Magnetic Disk Failure 156

        Flash Device Failure 157

        Host Failure 158

        Network Partition 159

        Disk Full Scenario 164

    Thin Provisioning Considerations 165

    vCenter Management 166

        vCenter Server Failure Scenario 167

        Running vCenter Server on VSAN 168

        Bootstrapping vCenter Server 168

    Summary 171

Chapter 8 Interoperability 173

    vMotion 174

    Storage vMotion 174

    vSphere HA 175

        vSphere HA Communication Network 175

        vSphere HA Heartbeat Datastores 176

        vSphere HA Metadata 177

        vSphere HA Admission Control 177

        vSphere HA Recommended Settings 177

        vSphere HA Protecting VSAN and Non-VSAN VMs 178

    Distributed Resource Scheduler 178

    Storage DRS 179

    Storage I/O Control 179

    Distributed Power Management 180

    VMware Data Protection 180

        Backup VMs from a VSAN Datastore Using VDP 181

        Restore VMs to a VSAN Datastore Using VDP 181

    vSphere Replication 183

        Replicate to VSAN at a Recovery Site 183

        Recover Virtual Machine 184

    Virtual Machine Snapshots 185

    vCloud Director 185

    VMware Horizon View 186

        VSAN Support for Horizon View 186

        VM Storage Policies on VMware View 187

        View Confi guration 187

        Changing the Default Policy 190

        Other View Considerations 190

    vCenter Operations 191

    vSphere 5.5 62TB VMDK 192

    Fault Tolerance 192

    Stretched/vSphere Metro Storage Cluster 193

    PowerCLI 193

    C# Client 193

    vCloud Automation Service 193

    Host Profi les 194

    Auto-Deploy 194

    Raw Device Mappings 195

    vSphere Storage APIs for Array Integration 195

    Microsoft Clustering Services 195

    Summary 195

Chapter 9 Designing a VSAN Cluster 197

    Sizing Constraints 197

    Failures to Tolerate = 1, Stripe Width = 1 199

    Flash to Magnetic Disk Ratio 200

    Designing for Performance 201

        Impact of the Disk Controller 202

    VSAN Performance Capabilities 206

        VMware View Performance 207

    Design and Sizing Tools 208

    Scenario 1: Where to Start 209

        Determining Your Host Confi guration 211

    Scenario 2 213

        Determining Your Host Confi guration 215

    Scenario 3 217

        Determining Your Host Confi guration 218

    Summary 220

Chapter 10 Troubleshooting, Monitoring, and Performance 221

    ESXCLI 221

        esxcli vsan datastore 222

        esxcli vsan network 223

        esxcli vsan storage 224

        esxcli vsan cluster 226

        esxcli vsan maintenancemode 227

        esxcli vsan policy 228

        esxcli vsan trace 230

        Additional Non-ESXCLI Commands for Troubleshooting VSAN 231

    Ruby vSphere Console 236

        VSAN Commands 237

        SPBM Commands 256

        PowerCLI for VSAN 259

    VSAN and SPBM APIs 261

        Enable/Disable VSAN (Automatic Claiming) 261

        Manual Disk Claiming 261

        Change the VM Storage Policy 262

        Enter Maintenance Mode 262

        Create and Delete Directories on a VSAN Datastore 262

        CMMDS 262

        SPBM 263

    Troubleshooting VSAN on the ESXi 263

        Log Files 263

        VSAN Traces 264

        VSAN VMkernel Modules and Drivers 264

    Performance Monitoring 265

        ESXTOP Performance Counters for VSAN 265

        vSphere Web Client Performance Counters for VSAN 266

        VSAN Observer 267

    Sample VSAN Observer Use Case 273

    Summary 276

TOC, 9780133854992, 7/3/14

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