6.5.1

Table Of Contents
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Configuring Discovery Addresses for iSCSI Adapters
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Configuring CHAP Parameters for iSCSI Adapters
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Configuring Advanced Parameters for iSCSI
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iSCSI Session Management
ESXi iSCSI SAN Requirements
To work properly with a SAN, your ESXi host must meet several requirements.
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Verify that your ESXi systems support the SAN storage hardware and firmware. For an up-to-date list,
see VMware Compatibility Guide.
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Configure your system to have only one VMFS datastore for each LUN.
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Unless you are using diskless servers, set up a diagnostic partition on local storage. If you have
diskless servers that boot from iSCSI SAN, see General Recommendations for Boot from iSCSI SAN
for information about diagnostic partitions with iSCSI.
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Use RDMs for access to any raw disk. For information, see Chapter 19 Raw Device Mapping.
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Set the SCSI controller driver in the guest operating system to a large enough queue. For information
on changing queue depth for iSCSI adapters and virtual machines, see vSphere Troubleshooting.
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On virtual machines running Microsoft Windows, increase the value of the SCSI TimeoutValue
parameter. With this parameter set up, the Windows VMs can better tolerate delayed I/O resulting
from a path failover. For information, see Set Timeout on Windows Guest OS.
ESXi iSCSI SAN Restrictions
A number of restrictions exist when you use ESXi with an iSCSI SAN.
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ESXi does not support iSCSI-connected tape devices.
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You cannot use virtual-machine multipathing software to perform I/O load balancing to a single
physical LUN.
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ESXi does not support multipathing when you combine independent hardware adapters with either
software or dependent hardware adapters.
Setting LUN Allocations for iSCSI
When preparing your ESXi system to use iSCSI SAN storage you need to set LUN allocations.
Note the following points:
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Storage Provisioning. To ensure that the host recognizes LUNs at startup time, configure all iSCSI
storage targets so that your host can access them and use them. Also, configure your host so that it
can discover all available iSCSI targets.
vSphere Storage
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