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
Even though the device and datastores are unavailable, virtual machines remain responsive. You can
power off the virtual machines or migrate them to a different datastore or host.
If later the device paths become operational, the host can resume I/O to the device and end the special
APD treatment.
Disable Storage APD Handling
The storage all paths down (APD) handling on your ESXi host is enabled by default. When it is enabled,
the host continues to retry nonvirtual machine I/O commands to a storage device in the APD state for a
limited time period. When the time period expires, the host stops its retry attempts and terminates any
nonvirtual machine I/O. You can disable the APD handling feature on your host.
If you disable the APD handling, the host will indefinitely continue to retry issued commands in an attempt
to reconnect to the APD device. This behavior might cause virtual machines on the host to exceed their
internal I/O timeout and become unresponsive or fail. The host might become disconnected from vCenter
Server.
Procedure
1 Navigate to the host.
2 Click the Configure tab.
3 Under System, click Advanced System Settings.
4 In the Advanced System Settings table, select the Misc.APDHandlingEnable parameter and click
the Edit icon.
5 Change the value to 0.
If you disabled the APD handling, you can reenable it and set its value to 1 when a device enters the APD
state. The internal APD handling feature turns on immediately and the timer starts with the current
timeout value for each device in APD.
Change Timeout Limits for Storage APD
The timeout parameter controls how many seconds the ESXi host must retry the I/O commands to a
storage device in an all paths down (APD) state. You can change the default timeout value.
The timeout period begins immediately after the device enters the APD state. After the timeout ends, the
host marks the APD device as unreachable. The host stops its attempts to retry any I/O that is not coming
from virtual machines. The host continues to retry virtual machine I/O.
By default, the timeout parameter on your host is set to 140 seconds. You can increase the value of the
timeout if, for example, storage devices connected to your ESXi host take longer than 140 seconds to
recover from a connection loss.
Note If you change the timeout parameter after the device becomes unavailable, the change does not
take effect for that particular APD incident.
vSphere Storage
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