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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
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Change LUN IDs only when VMFS datastores deployed on the LUNs have no running virtual
machines. If you change the ID, virtual machines running on the VMFS datastore might fail.
After you change the ID of the LUN, you must rescan your storage to reset the ID on your host. For
information on using the rescan, see Storage Rescan Operations.
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If you change the default iSCSI name of your iSCSI adapter, make sure that the name you enter is
worldwide unique and properly formatted. To avoid storage access problems, never assign the same
iSCSI name to different adapters, even on different hosts.
Optimizing iSCSI SAN Storage Performance
Several factors contribute to optimizing a typical SAN environment.
If the network environment is properly configured, the iSCSI components provide adequate throughput
and low enough latency for iSCSI initiators and targets. If the network is congested and links, switches or
routers are saturated, iSCSI performance suffers and might not be adequate for ESXi environments.
Storage System Performance
Storage system performance is one of the major factors contributing to the performance of the entire
iSCSI environment.
If issues occur with storage system performance, consult your storage system vendor’s documentation for
any relevant information.
When you assign LUNs, remember that you can access each shared LUN through a number of hosts,
and that a number of virtual machines can run on each host. One LUN used by the ESXi host can service
I/O from many different applications running on different operating systems. Because of this diverse
workload, the RAID group that contains the ESXi LUNs should not include LUNs that other hosts use that
are not running ESXi for I/O intensive applications.
Enable read caching and write caching.
Load balancing is the process of spreading server I/O requests across all available SPs and their
associated host server paths. The goal is to optimize performance in terms of throughput (I/O per second,
megabytes per second, or response times).
SAN storage systems require continual redesign and tuning to ensure that I/O is load balanced across all
storage system paths. To meet this requirement, distribute the paths to the LUNs among all the SPs to
provide optimal load balancing. Close monitoring indicates when it is necessary to manually rebalance
the LUN distribution.
Tuning statically balanced storage systems is a matter of monitoring the specific performance statistics
(such as I/O operations per second, blocks per second, and response time) and distributing the LUN
workload to spread the workload across all the SPs.
Server Performance with iSCSI
To ensure optimal ESXi host performance, consider several factors.
vSphere Storage
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