6.7
Table Of Contents
- vSphere Storage
- Contents
- About vSphere Storage
- Introduction to Storage
- Getting Started with a Traditional Storage Model
- Overview of Using ESXi with a SAN
- Using ESXi with Fibre Channel SAN
- Configuring Fibre Channel Storage
- Configuring Fibre Channel over Ethernet
- Booting ESXi from Fibre Channel SAN
- Booting ESXi with Software FCoE
- Best Practices for Fibre Channel Storage
- Using ESXi with iSCSI SAN
- Configuring iSCSI Adapters and Storage
- ESXi iSCSI SAN Recommendations and Restrictions
- Configuring iSCSI Parameters for Adapters
- Set Up Independent Hardware iSCSI Adapters
- Configure Dependent Hardware iSCSI Adapters
- Configure the Software iSCSI Adapter
- Configure iSER Adapters
- Modify General Properties for iSCSI or iSER Adapters
- Setting Up Network for iSCSI and iSER
- Using Jumbo Frames with iSCSI
- Configuring Discovery Addresses for iSCSI Adapters
- Configuring CHAP Parameters for iSCSI Adapters
- Configuring Advanced Parameters for iSCSI
- iSCSI Session Management
- Booting from iSCSI SAN
- Best Practices for iSCSI Storage
- Managing Storage Devices
- Storage Device Characteristics
- Understanding Storage Device Naming
- Storage Rescan Operations
- Identifying Device Connectivity Problems
- Enable or Disable the Locator LED on Storage Devices
- Erase Storage Devices
- Working with Flash Devices
- About VMware vSphere Flash Read Cache
- Working with Datastores
- Types of Datastores
- Understanding VMFS Datastores
- Upgrading VMFS Datastores
- Understanding Network File System Datastores
- Creating Datastores
- Managing Duplicate VMFS Datastores
- Increasing VMFS Datastore Capacity
- Administrative Operations for Datastores
- Set Up Dynamic Disk Mirroring
- Collecting Diagnostic Information for ESXi Hosts on a Storage Device
- Checking Metadata Consistency with VOMA
- Configuring VMFS Pointer Block Cache
- Understanding Multipathing and Failover
- Failovers with Fibre Channel
- Host-Based Failover with iSCSI
- Array-Based Failover with iSCSI
- Path Failover and Virtual Machines
- Pluggable Storage Architecture and Path Management
- Viewing and Managing Paths
- Using Claim Rules
- Scheduling Queues for Virtual Machine I/Os
- Raw Device Mapping
- Storage Policy Based Management
- Virtual Machine Storage Policies
- Workflow for Virtual Machine Storage Policies
- Populating the VM Storage Policies Interface
- About Rules and Rule Sets
- Creating and Managing VM Storage Policies
- About Storage Policy Components
- Storage Policies and Virtual Machines
- Default Storage Policies
- Using Storage Providers
- Working with Virtual Volumes
- About Virtual Volumes
- Virtual Volumes Concepts
- Virtual Volumes and Storage Protocols
- Virtual Volumes Architecture
- Virtual Volumes and VMware Certificate Authority
- Snapshots and Virtual Volumes
- Before You Enable Virtual Volumes
- Configure Virtual Volumes
- Provision Virtual Machines on Virtual Volumes Datastores
- Virtual Volumes and Replication
- Best Practices for Working with vSphere Virtual Volumes
- Troubleshooting Virtual Volumes
- Filtering Virtual Machine I/O
- Storage Hardware Acceleration
- Hardware Acceleration Benefits
- Hardware Acceleration Requirements
- Hardware Acceleration Support Status
- Hardware Acceleration for Block Storage Devices
- Hardware Acceleration on NAS Devices
- Hardware Acceleration Considerations
- Thin Provisioning and Space Reclamation
- Using vmkfstools
- vmkfstools Command Syntax
- The vmkfstools Command Options
- -v Suboption
- File System Options
- Virtual Disk Options
- Supported Disk Formats
- Creating a Virtual Disk
- Initializing a Virtual Disk
- Inflating a Thin Virtual Disk
- Converting a Zeroedthick Virtual Disk to an Eagerzeroedthick Disk
- Removing Zeroed Blocks
- Deleting a Virtual Disk
- Renaming a Virtual Disk
- Cloning or Converting a Virtual Disk or RDM
- Extending a Virtual Disk
- Upgrading Virtual Disks
- Creating a Virtual Compatibility Mode Raw Device Mapping
- Creating a Physical Compatibility Mode Raw Device Mapping
- Listing Attributes of an RDM
- Displaying Virtual Disk Geometry
- Checking and Repairing Virtual Disks
- Checking Disk Chain for Consistency
- Storage Device Options
Raw Device Mapping 19
Raw device mapping (RDM) provides a mechanism for a virtual machine to have direct access to a LUN
on the physical storage subsystem.
The following topics contain information about RDMs and provide instructions on how to create and
manage RDMs.
This chapter includes the following topics:
n
About Raw Device Mapping
n
Raw Device Mapping Characteristics
n
Create Virtual Machines with RDMs
n
Manage Paths for a Mapped LUN
About Raw Device Mapping
An RDM is a mapping file in a separate VMFS volume that acts as a proxy for a raw physical storage
device. With the RDM, a virtual machine can access and use the storage device directly. The RDM
contains metadata for managing and redirecting disk access to the physical device.
The file gives you some of the advantages of direct access to a physical device, but keeps some
advantages of a virtual disk in VMFS. As a result, it merges the VMFS manageability with the raw device
access.
Figure 19‑1. Raw Device Mapping
VMFS volume
Virtual
machine
address
resolution
opens
reads,
writes
mapped device
mapping file
VMware, Inc.
232