6.0.1
Table Of Contents
- vSphere Storage
- Contents
- About vSphere Storage
- Updated Information
- Introduction to Storage
- 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
- Dependent Hardware iSCSI Considerations
- Configure 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 Refresh and Rescan Operations
- Identifying Device Connectivity Problems
- Edit Configuration File Parameters
- Enable or Disable the Locator LED on Storage Devices
- Working with Flash Devices
- About VMware vSphere Flash Read Cache
- Working with Datastores
- Understanding VMFS Datastores
- Understanding Network File System Datastores
- Creating Datastores
- Managing Duplicate VMFS Datastores
- Upgrading 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
- Working with Virtual Volumes
- Virtual Machine Storage Policies
- Upgrading Legacy Storage Profiles
- Understanding Virtual Machine Storage Policies
- Working with Virtual Machine Storage Policies
- Creating and Managing VM Storage Policies
- Storage Policies and Virtual Machines
- Default Storage Policies
- 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
- Filtering Virtual Machine I/O
- VMkernel and Storage
- 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
- Storage Thick and Thin Provisioning
- Using Storage Providers
- Using vmkfstools
- vmkfstools Command Syntax
- vmkfstools Options
- -v Suboption
- File System Options
- Virtual Disk Options
- Supported Disk Formats
- Creating a Virtual Disk
- Example for Creating a Virtual Disk
- Initializing a Virtual Disk
- Inflating a Thin Virtual Disk
- Removing Zeroed Blocks
- Converting a Zeroedthick Virtual Disk to an Eagerzeroedthick Disk
- Deleting a Virtual Disk
- Renaming a Virtual Disk
- Cloning or Converting a Virtual Disk or RDM
- Example for Cloning or Converting a Virtual Disk
- Migrate Virtual Machines Between DifferentVMware Products
- Extending a Virtual Disk
- Upgrading Virtual Disks
- Creating a Virtual Compatibility Mode Raw Device Mapping
- Example for Creating a Virtual Compatibility Mode RDM
- 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
- Index
Because each application has dierent requirements, you can meet these goals by choosing an appropriate
RAID group on the storage system. To achieve performance goals, perform the following tasks:
n
Place each LUN on a RAID group that provides the necessary performance levels. Pay aention to the
activities and resource utilization of other LUNS in the assigned RAID group. A high-performance
RAID group that has too many applications doing I/O to it might not meet performance goals required
by an application running on the ESXi host.
n
Provide each server with a sucient number of network adapters or iSCSI hardware adapters to allow
maximum throughput for all the applications hosted on the server for the peak period. I/O spread
across multiple ports provides higher throughput and less latency for each application.
n
To provide redundancy for software iSCSI, make sure the initiator is connected to all network adapters
used for iSCSI connectivity.
n
When allocating LUNs or RAID groups for ESXi systems, multiple operating systems use and share that
resource. As a result, the performance required from each LUN in the storage subsystem can be much
higher if you are working with ESXi systems than if you are using physical machines. For example, if
you expect to run four I/O intensive applications, allocate four times the performance capacity for the
ESXi LUNs.
n
When using multiple ESXi systems in conjunction with vCenter Server, the performance needed from
the storage subsystem increases correspondingly.
n
The number of outstanding I/Os needed by applications running on an ESXi system should match the
number of I/Os the SAN can handle.
Network Performance
A typical SAN consists of a collection of computers connected to a collection of storage systems through a
network of switches. Several computers often access the same storage.
Single Ethernet Link Connection to Storage shows several computer systems connected to a storage system
through an Ethernet switch. In this conguration, each system is connected through a single Ethernet link to
the switch, which is also connected to the storage system through a single Ethernet link. In most
congurations, with modern switches and typical trac, this is not a problem.
Figure 12‑1. Single Ethernet Link Connection to Storage
When systems read data from storage, the maximum response from the storage is to send enough data to ll
the link between the storage systems and the Ethernet switch. It is unlikely that any single system or virtual
machine gets full use of the network speed, but this situation can be expected when many systems share one
storage device.
Chapter 12 Best Practices for iSCSI Storage
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