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Table Of Contents
Software iSCSI Adapter
A software iSCSI adapter is a VMware code built into the VMkernel. Using the software iSCSI adapter,
your host can connect to the iSCSI storage device through standard network adapters. The software
iSCSI adapter handles iSCSI processing while communicating with the network adapter. With the
software iSCSI adapter, you can use iSCSI technology without purchasing specialized hardware.
Hardware iSCSI Adapter
A hardware iSCSI adapter is a third-party adapter that offloads iSCSI and network processing from your
host. Hardware iSCSI adapters are divided into categories.
Dependent Hardware
iSCSI Adapter
Depends on VMware networking, and iSCSI configuration and
management interfaces provided by VMware.
This type of adapter can be a card that presents a standard network
adapter and iSCSI offload functionality for the same port. The iSCSI offload
functionality depends on the host's network configuration to obtain the IP,
MAC, and other parameters used for iSCSI sessions. An example of a
dependent adapter is the iSCSI licensed Broadcom 5709 NIC.
Independent Hardware
iSCSI Adapter
Implements its own networking and iSCSI configuration and management
interfaces.
Typically, an independent hardware iSCSI adapter is a card that either
presents only iSCSI offload functionality or iSCSI offload functionality and
standard NIC functionality. The iSCSI offload functionality has independent
configuration management that assigns the IP, MAC, and other parameters
used for the iSCSI sessions. An example of an independent adapter is the
QLogic QLA4052 adapter.
Hardware iSCSI adapters might need to be licensed. Otherwise, they might not appear in the client or
vSphere CLI. Contact your vendor for licensing information.
About the VMware iSER Adapter
In addition to traditional iSCSI, ESXi supports the iSCSI Extensions for RDMA (iSER) protocol. When the
iSER protocol is enabled, the iSCSI framework on the ESXi host can use the Remote Direct Memory
Access (RDMA) transport instead of TCP/IP.
The traditional iSCSI protocol carries SCSI commands over a TCP/IP network between an iSCSI initiator
on a host and an iSCSI target on a storage device. The iSCSI protocol encapsulates the commands and
assembles that data in packets for the TCP/IP layer. When the data arrives, the iSCSI protocol
disassembles the TCP/IP packets, so that the SCSI commands can be differentiated and delivered to the
storage device.
vSphere Storage
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