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Table Of Contents
Best Practices for iSCSI Storage 13
When using ESXi with the iSCSI SAN, follow recommendations that VMware offers to avoid problems.
Check with your storage representative if your storage system supports Storage API - Array Integration
hardware acceleration features. If it does, refer to your vendor documentation to enable hardware
acceleration support on the storage system side. For more information, see Chapter 24 Storage
Hardware Acceleration.
This chapter includes the following topics:
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Preventing iSCSI SAN Problems
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Optimizing iSCSI SAN Storage Performance
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Checking Ethernet Switch Statistics
Preventing iSCSI SAN Problems
When using ESXi with a SAN, you must follow specific guidelines to avoid SAN problems.
Observe the following tips:
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Place only one VMFS datastore on each LUN.
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Do not change the path policy the system sets for you unless you understand the implications of
making such a change.
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Document everything. Include information about configuration, access control, storage, switch, server
and iSCSI HBA configuration, software and firmware versions, and storage cable plan.
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Plan for failure:
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Make several copies of your topology maps. For each element, consider what happens to your
SAN if the element fails.
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Cross off different links, switches, HBAs, and other elements to ensure that you did not miss a
critical failure point in your design.
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Ensure that the iSCSI HBAs are installed in the correct slots in the ESXi host, based on slot and bus
speed. Balance PCI bus load among the available buses in the server.
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Become familiar with the various monitor points in your storage network, at all visibility points,
including ESXi performance charts, Ethernet switch statistics, and storage performance statistics.
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