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iSCSI Optimization
This chapter describes how to configure internet small computer system interface (iSCSI) optimization,
which enables quality-of-service (QoS) treatment for iSCSI traffic. The topics covered in this chapter
include:
•iSCSI Optimization
•Default iSCSI Optimization Values
•iSCSI Optimization Prerequisites
•Configuring iSCSI Optimization
•Displaying iSCSI Optimization Information

iSCSI Optimization Overview

iSCSI is a TCP/IP-based protocol for establishing and managing connections between IP-based storage
devices and initiators in a storage area network (SAN).
iSCSI optimization enables the network switch to auto-detect Dell’s iSCSI storage arrays and triggers a
self-configuration of several key network configurations that enables optimization of the network for
better storage traffic throughput. iSCSI is disabled by default on the Z9500 platform.
iSCSI optimization also provides a means of monitoring iSCSI sessions and applying quality of service
(QoS) policies on iSCSI traffic. When enabled, iSCSI optimization allows a switch to monitor (snoop) the
establishment and termination of iSCSI connections. The switch uses the snooped information to detect
iSCSI sessions and connections established through the switch.
iSCSI optimization allows you to reduce deployment time and management complexity in data centers.
In a data center network, Dell EqualLogic and Compellent iSCSI storage arrays are connected to a
converged Ethernet network using the data center bridging exchange protocol (DCBx) through stacked
and/or non-stacked Ethernet switches.
iSCSI session monitoring over virtual link trunking (VLT) synchronizes the iSCSI session information
between the VLT peers, allowing session information to be available in both the VLT peers. You can
enable or disable iSCSI when you configure VLT.
iSCSI optimization functions as follows:
• Auto-detection of EqualLogic storage arrays — the switch detects any active EqualLogic array directly
attached to its ports.
• Manual configuration to detect Compellent storage arrays where auto-detection is not supported.
• Automatic configuration of switch ports after detection of storage arrays.
• If you configure flow-control, iSCSI uses the current configuration. If you do not configure flow-
control, iSCSI auto-configures flow control settings so that receive-only is enabled and transmit-only
is disabled. .
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