6.5.1
Table Of Contents
- vSphere Storage
- Contents
- About vSphere Storage
- Updated Information
- 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 Requirements
- ESXi iSCSI SAN Restrictions
- Setting LUN Allocations for iSCSI
- Network Configuration and Authentication
- Set Up Independent Hardware iSCSI Adapters
- About Dependent Hardware iSCSI Adapters
- About the Software iSCSI Adapter
- Modify General Properties for iSCSI Adapters
- Setting Up iSCSI Network
- 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
- Edit Configuration File Parameters
- 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
- 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
- Raw Device Mapping
- Software-Defined Storage and Storage Policy Based Management
- About Storage Policy Based Management
- Virtual Machine Storage Policies
- Working with Virtual Machine Storage Policies
- Populating the VM Storage Policies Interface
- Default Storage Policies
- Creating and Managing VM Storage Policies
- Storage Policies and Virtual Machines
- Assign Storage Policies to Virtual Machines
- Change Storage Policy Assignment for Virtual Machine Files and Disks
- Monitor Storage Compliance for Virtual Machines
- Check Compliance for a VM Storage Policy
- Find Compatible Storage Resource for Noncompliant Virtual Machine
- Reapply Virtual Machine Storage Policy
- 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
- 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
Thin Provisioning and Space
Reclamation 25
vSphere supports two models of storage provisioning, thick provisioning and thin provisioning.
Thick provisioning It is a traditional model of the storage provisioning. With the thick
provisioning, large amount of storage space is provided in advance in
anticipation of future storage needs. However, the space might remain
unused causing underutilization of storage capacity.
Thin provisioning This method contrast with thick provisioning and helps you eliminate
storage underutilization problems by allocating storage space in a flexible
on-demand manner. With ESXi, you can use two models of thin
provisioning, array‐level and virtual disk‐level.
Thin provisioning allows you to report more virtual storage space than there
is real physical capacity. This discrepancy can lead to storage over-
subscription, also called over-provisioning. When you use thin provisioning,
monitor actual storage usage to avoid conditions when you run out of
physical storage space.
This chapter includes the following topics:
n
Virtual Disk Thin Provisioning
n
ESXi and Array Thin Provisioning
n
Storage Space Reclamation
Virtual Disk Thin Provisioning
When you create a virtual machine, a certain amount of storage space on a datastore is provisioned to
virtual disk files.
By default, ESXi offers a traditional storage provisioning method for virtual machines. With this method,
you first estimate how much storage the virtual machine might need for its entire life cycle. You then
provision a fixed amount of storage space to the VM virtual disk in advance, for example, 40 GB. The
entire provisioned space is committed to the virtual disk. A virtual disk that immediately occupies the
entire provisioned space is a thick disk.
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