THE ONLY AUTHORITATIVE, COMPREHENSIVE GUIDE TO VSPHERE STORAGE IMPLEMENTATION AND MANAGEMENT

Effective VMware virtualization storage planning and management has become crucial-but it can be extremely complex. Now, the leading VMware expert on storage completely demystifies the "black box" of vSphere storage and provides illustrated, step-by-step procedures for performing every key task associated with it. You'll gain the deep understanding you need to make better storage decisions, solve problems, and keep problems from occurring in the first place.

Mostafa Khalil presents techniques based on years of personal experience helping customers troubleshoot storage in their vSphere production environments. With more experience than anyone else in the field, he combines expert guidelines, insights for better architectural design, best practices for both planning and management, common configuration details, and deep dives into both vSphere and third-party storage.

Storage Implementation in vSphere® 5.0 fully explains each storage connectivity choice and protocol supported by VMware, introduces Pluggable Storage Architecture (PSA), and shows how to build on PSA with multipathing, failover, and ALUA. It thoroughly introduces Storage Virtualization Devices (SVDs) and VMDirectPath I/O, and shows how to drive powerful improvements in performance, flexibility, and manageability with VMFS 5 and VAAI.

COVERAGE INCLUDES

• Understanding how FC, FCoE, and iSCSI interact with VMware vSphere 5

• Implementing specific VMware capabilities on storage hardware from each leading vendor

• Avoiding, recognizing, and fixing misconfigurations and other problems

• Using third-party MPIO plug-ins certified with vSphere 5 and PSA

• Maximizing availability through multipathing and failover

• Implementing fixed and round-robin multipathing on arrays with ALUA support

• Monitoring and optimizing virtual storage performance

• Managing vSphere-compatible file systems: VMFS and NFS

• Taking full advantage of VMDirectPath I/O

• Implementing heterogeneous storage configurations

• Presenting abstracted storage through virtual disks and Raw Device Mappings (RDMs)

• Using VMFS 5 to simplify management and improve scalability in large-scale environments

• Sharing storage and migrating more easily across multiple VMware vSphere instances

• Optimizing storage performance with VAAI-compliant devices

Mostafa Khalil, Senior Staff Engineer with VMware Global Support Services, specializes in storage integration for virtual environments. He has worked for VMware for 13 years and supported all VMware virtualization products since Workstation for Linux 1.0 beta. Khalil has worked on most enterprise storage vendors' solutions and received engineering-level training for many of them. He has presented at every VMworld, and at VMware Partner Exchange, VMware User Group, and USENIX.

ISBN-13: 978-0-321-79993-7

ISBN-10: 0-321-79993-3

Mostafa Khalil is a senior staff engineer at VMware. He is a senior member of VMware Global Support Services and has worked for VMware for more than 13 years. Prior to joining VMware, he worked at Lotus/IBM. A native of Egypt, Mostafa graduated from the Al-Azhar University's School of Medicine, and practiced medicine in Cairo. He became intrigued by the mini computer system used in his medical practice and began to educate himself about computing and networking technologies. After moving to the United States, Mostafa continued to focus on computing and acquired several professional certifications. He is certified as VCDX (3, 4, & 5), VCAP (4 & 5)-DCD, VCAP4-DCA, VCP (2, 3, 4, & 5), MCSE, Master CNE, HP ASE, IBM CSE, and Lotus CLP. As storage became a central element in the virtualization environment, Mostafa became an expert in this field and delivered several seminars and troubleshooting workshops at various VMware public events in the United States and around the world.

Part I: Storage Protocols and Block Devices

Chapter 1 Storage Types 1

History of Storage 1

Birth of the Hard Disks 4

Along Comes SCSI 4

PATA and SATA-SCSI's Distant Cousins? 5

Units of Measuring Storage Capacity 7

Permanent Storage Media Relevant to vSphere 5 8

Chapter 2 Fibre Channel Storage Connectivity 11

SCSI Standards and Protocols 11

SCSI-2 and SCSI-3 Standards 11

Fibre Channel Protocol 12

Decoding EMC Symmetrix WWPN 25

Locating Targets' WWNN and WWPN Seen by vSphere 5 Hosts 27

SAN Topology 30

Fabric Switches 35

FC Zoning 37

Designing Storage with No Single Points of Failure 41

Chapter 3 FCoE Storage Connectivity 49

FCoE (Fibre Channel over Ethernet) 49

FCoE Initialization Protocol 51

FCoE Initiators 54

Hardware FCoE Adapter 54

Software FCoE Adapter 55

Overcoming Ethernet Limitations 56

Flow Control in FCoE 57

Protocols Required for FCoE 58

Priority-Based Flow Control 58

Enhanced Transmission Selection 58

Data Center Bridging Exchange 59

10GigE - A Large Pipeline 59

802.1p Tag 60

Hardware FCoE Adapters 62

How SW FCoE Is Implemented in ESXi 5 62

Configuring FCoE Network Connections 64

Enabling Software FCoE Adapter 68

Removing or Disabling a Software FCoE Adapter 71

Using the UI to Remove the SW FCoE Adapter 71

Using the CLI to Remove the SW FCoE Adapter 72

Troubleshooting FCoE 73

ESXCLI 73

FCoE-Related Logs 76

Parting Tips 82

Chapter 4 iSCSI Storage Connectivity 85

iSCSI Protocol 85

Chapter 5 vSphere Pluggable Storage Architecture (PSA) 165

Native Multipathing 166

Storage Array Type Plug-in (SATP) 167

How to List SATPs on an ESXi 5 Host 168

Path Selection Plugin (PSP) 169

How to List PSPs on an ESXi 5 Host 170

Third-Party Plug-ins 171

Multipathing Plugins (MPPs) 172

Anatomy of PSA Components 173

I/O Flow Through PSA and NMP 174

Classification of Arrays Based on How They Handle I/O 175

Paths and Path States 176

Preferred Path Setting 176

Flow of I/O Through NMP 178

Listing Multipath Details 179

Listing Paths to a LUN Using the UI 179

Listing Paths to a LUN Using the Command-Line Interface (CLI) 183

Identifying Path States and on Which Path the I/O Is Sent-FC 186

Example of Listing Paths to an iSCSI-Attached Device 187

Identifying Path States and on Which Path the I/O Is Sent-iSCSI 190

Example of Listing Paths to an FCoE-Attached Device 190

Identifying Path States and on Which Path the I/O Is Sent-FC 192

Claim Rules 192

MP Claim Rules 193

Plug-in Registration 196

SATP Claim Rules 197

Modifying PSA Plug-in Configurations Using the UI 201

Which PSA Configurations Can Be Modified Using the UI? 202

Modifying PSA Plug-ins Using the CLI 204

Available CLI Tools and Their Options 204

Adding a PSA Claim Rule 206

How to Delete a Claim Rule 215

How to Mask Paths to a Certain LUN 217

How to Unmask a LUN 219

Changing PSP Assignment via the CLI 220

Chapter 6 ALUA 227

ALUA Definition 228

ALUA Target Port Group 228

Asymmetric Access State 229

ALUA Management Modes 231

ALUA Followover 232

Identifying Device ALUA Configuration 237

Troubleshooting ALUA 243

Chapter 7 Multipathing and Failover 249

What Is a Path? 250

Where Is the Active Path? 255

Identifying the Current Path Using the CLI 255

Identifying the IO (Current) Path Using the UI 256

LUN Discovery and Path Enumeration 258

Sample LUN Discovery and Path Enumeration Log Entries 261

Factors Affecting Multipathing 265

How to Access Advanced Options 266

Failover Triggers 267

SCSI Sense Codes 267

Multipathing Failover Triggers 270

Path States 273

Factors Affecting Paths States 274

Path Selection Plug-ins 276

VMW_PSP_FIXED 276

VMW_PSP_MRU 277

VMW_PSP_RR 277

When and How to Change the Default PSP 277

When Should You Change the Default PSP? 277

How to Change the Default PSP 278

PDL and APD 280

Unmounting a VMFS Volume 281

Detaching the Device Whose Datastore Was Unmounted 286

Path Ranking 291

Path Ranking for ALUA and Non-ALUA Storage 291

How Does Path Ranking Work for ALUA Arrays? 292

How Does Path Ranking Work for Non-ALUA Arrays? 293

Configuring Ranked Paths 295

Chapter 8 Third-Party Multipathing I/O Plug-ins 297

MPIO Implementations on vSphere 5 297

EMC PowerPath/VE 5.7 298

Downloading PowerPath/VE 298

Downloading Relevant PowerPath/VE Documentations 300

PowerPath/VE Installation Overview 302

What Gets Installed? 303

Installation Using the Local CLI 304

Installation Using vMA 5.0 306

Verifying Installation 307

Listing Devices Claimed by PowerPath/VE 311

Managing PowerPath/VE 312

How to Uninstall PowerPath/VE 313

Hitachi Dynamic Link Manager (HDLM) 315

Obtaining Installation Files 316

Installing HDLM 317

Modifying HDLM PSP Assignments 322

Locating Certified Storage on VMware HCL 326

Dell EqualLogic PSP Routed 327

Downloading Documentation 328

Downloading the Installation File and the Setup Script 328

How Does It Work? 328

Installing EQL MEM on vSphere 5 329

Uninstalling Dell PSP EQL ROUTED MEM 331

Chapter 9 Using Heterogeneous Storage Configurations 333

What Is a "Heterogeneous" Storage Environment? 333

Scenarios of Heterogeneous Storage 334

ESXi 5 View of Heterogeneous Storage 335

Basic Rules of Using Heterogeneous Storage 335

Naming Convention 336

So, How Does This All Fit Together? 337

Chapter 10 Using VMDirectPath I/O 345

What Is VMDirectPath? 345

Which I/O Devices Are Supported? 346

Locating Hosts Supporting VMDirectPath IO on the HCL 348

VMDirectPath I/O Configuration 349

What Gets Added to the VM's Configuration File? 358

Practical Examples of VM Design Scenarios Utilizing VMDirectPath I/O 358

HP Command View EVA Scenario 358

Passing Through Physical Tape Devices 360

What About vmDirectPath Gen. 2? 360

How Does SR-IOV Work? 361

Supported VMDirectPath I/O Devices 364

Example of DirectPath IO Gen. 2 364

Troubleshooting VMDirectPath I/O 364

Interrupt Handling and IRQ Sharing 364

Device Sharing 365

Chapter 11 Storage Virtualization Devices (SVDs) 369

SVD Concept 369

How Does It Work? 370

Constraints 372

Front-End Design Choices 373

Back-End Design Choices 376

LUN Presentation Considerations 377

RDM (RAW Device Mapping) Considerations 378

Part II: File Systems

Chapter 12 VMFS Architecture 381

History of VMFS 382

VMFS 3 on Disk Layout 384

VMFS5 Layout 391

Common Causes of Partition Table Problems 398

Re-creating a Lost Partition Table for VMFS3 Datastores 399

Re-creating a Lost Partition Table for VMFS5 Datastores 404

Preparing for the Worst! Can You Recover from a File System Corruption? 410

Span or Grow? 416

Upgrading to VMFS5 430

Chapter 13 Virtual Disks and RDMs 437

The Big Picture 437

Virtual Disks 438

Virtual Disk Types 441

Thin on Thin 443

Virtual Disk Modes 444

Creating Virtual Disks Using the UI 445

Creating Virtual Disks During VM Creation 445

Creating a Virtual Disk After VM Creation 448

Creating Virtual Disks Using vmkfstools 450

Creating a Zeroed Thick Virtual Disk Using vmkfstools 452

Creating an Eager Zeroed Thick Virtual Disk Using vmkfstools 452

Creating a Thin Virtual Disk Using vmkfstools 454

Cloning Virtual Disks Using vmkfstools 456

Raw Device Mappings 459

Creating Virtual Mode RDMs Using the UI 459

Listing RDM Properties 466

Virtual Storage Adapters 472

Selecting the Type of Virtual Storage Adapter 473

VMware Paravirtual SCSI Controller 475

Virtual Machine Snapshots 477

Creating the VM's First Snapshot While VM Is Powered Off 478

Creating a VM Second Snapshot While Powered On 484

Snapshot Operations 488

Go to a Snapshot Operation 489

Delete a Snapshot Operation 492

Consolidate Snapshots Operation 494

Reverting to Snapshot 499

Linked Clones 501

Chapter 14 Distributed Locks 505

Basic Locking 506

What Happens When a Host Crashes? 507

Optimistic Locking 508

Dynamic Resource Allocation 509

SAN Aware Retries 509

Optimistic I/O 511

List of Operations That Require SCSI Reservations 511

MSCS-Related SCSI Reservations 512

Perennial Reservations 514

Under the Hood of Distributed Locks 519

Chapter 15 Snapshot Handling 529

What Is a Snapshot? 530

What Is a Replica? 530

What Is a Mirror? 530

VMFS Signature 531

Listing Datastores' UUIDs via the Command-Line Interface 532

Effects of Snapshots on VMFS Signature 532

How to Handle VMFS Datastore on Snapshot LUNs 533

Resignature 534

Resignature a VMFS Datastore Using the UI 534

Resignature a VMFS Datastore Using ESXCLI 536

Force Mount 540

Force-Mounting VMFS Snapshot Using ESXCLI 541

Sample Script to Force-Mount All Snapshots on Hosts in a Cluster 543

Chapter 16 VAAI 549

What Is VAAI? 550

VAAI Primitives 550

Hardware Acceleration APIs 550

Thin Provisioning APIs 551

Full Copy Primitive (XCOPY) 551

Block Zeroing Primitive (WRITE_SAME) 552

Hardware Accelerated Locking Primitive (ATS) 553

ATS Enhancements on VMFS5 553

Thin Provisioned APIs 554

NAS VAAI Primitives 555

Enabling and Disabling Primitives 555

Disabling Block Device Primitives Using the UI 557

Disabling Block Device VAAI Primitives Using the CLI 559

Disabling the UNMAP Primitive Using the CLI 562

Disabling NAS VAAI Primitives 562

VAAI Plug-ins and VAAI Filter 564

Locating Supported VAAI-Capable Block Devices 565

Locating Supported VAAI-Capable NAS Devices 567

Listing Registered Filter and VAAI Plug-ins 569

Listing VAAI Filters and Plug-ins Configuration 570

Listing VAAI vmkernel Modules 573

Identifying VAAI Primitives Supported by a Device 574

Listing Block Device VAAI Support Status Using the CLI 574

Listing NAS Device VAAI Support Status 577

Listing VAAI Support Status Using the UI 577

Displaying Block Device VAAI I/O Stats Using ESXTOP 579

The VAAI T10 Standard Commands 582

Troubleshooting VAAI Primitives 583

Index 587