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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:
•
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Default iSCSI Optimization Values
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iSCSI Optimization Prerequisites
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Configuring iSCSI Optimization
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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.
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:
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Auto-detection of EqualLogic storage arrays — the switch detects any active EqualLogic array directly attached to its ports.
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Manual configuration to detect Compellent storage arrays where auto-detection is not supported.
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Automatic configuration of switch ports after detection of storage arrays.
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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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iSCSI monitoring sessions — the switch monitors and tracks active iSCSI sessions in connections on the switch, including port
information and iSCSI session information.
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iSCSI QoS — A user-configured iSCSI class of service (CoS) profile is applied to all iSCSI traffic. Classifier rules are used to direct
the iSCSI data traffic to queues that can be given preferential QoS treatment over other data passing through the switch.
Preferential treatment helps to avoid session interruptions during times of congestion that would otherwise cause dropped iSCSI
packets.
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iSCSI DCBx TLVs are supported.
The following illustration shows iSCSI optimization between servers and a storage array in which a stack of three switches connect
installed servers (iSCSI initiators) to a storage array (iSCSI targets) in a SAN network. iSCSI optimization running on the master
iSCSI Optimization
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Summary of Contents for S4048-ON
Page 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Page 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Page 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Page 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Page 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Page 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Page 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Page 633: ...Policy based Routing PBR 633 ...
Page 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Page 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...