Users Guide

You can configure the switch to monitor traffic for additional port numbers or a combination of port number and target IP address, and
you can remove the well-known port numbers from monitoring.
Information Monitored in iSCSI Traffic Flows
iSCSI optimization examines the following data in packets and uses the data to track the session and create the classifier entries that
enable QoS treatment:
• Initiator’s IP Address
• Target’s IP Address
• ISID (Initiator defined session identifier)
• Initiator’s IQN (iSCSI qualified name)
• Target’s IQN
• Initiator’s TCP Port
• Target’s TCP Port
If no iSCSI traffic is detected for a session during a user-configurable aging period, the session data clears.
Detection and Auto configuration for Dell EqualLogic
Arrays
The iSCSI optimization feature includes auto-provisioning support with the ability to detect directly connected Dell EqualLogic storage
arrays and automatically reconfigure the switch to enhance storage traffic flows.
An Aggregator uses the link layer discovery protocol (LLDP) to discover Dell EqualLogic devices on the network. LLDP is enabled by
default. For more information about LLDP, refer to Link Layer Discovery Protocol (LLDP)
The following message displays the first time a Dell EqualLogic array is detected and describes the configuration change that are
automatically performed:
%STKUNIT0-M:CP %IFMGR-5-IFM_ISCSI_AUTO_CONFIG: This switch is being configured
for optimal conditions to support iSCSI traffic which will cause some automatic
configuration to occur including jumbo frames and flow-control on all ports; no
storm control to be enabled on the port of detection.
The following syslog message is generated the first time an EqualLogic array is detected:
%STKUNIT0-M:CP %LLDP-5-LLDP_EQL_DETECTED: EqualLogic Storage Array detected on
interface Te 1/43
• At the first detection of an EqualLogic array, a maximum transmission unit (MTU) of 12000 is enabled on all ports and port-channels (if
it has not already been enabled).
• Unicast storm control is disabled on the interface identified by LLDP.
iSCSI Optimization: Operation
When the Aggregator auto-configures with iSCSI enabled, the following occurs:
• Link-level flow control is enabled on PFC disabled interfaces.
• iSCSI session snooping is enabled.
• iSCSI LLDP monitoring starts to automatically detect EqualLogic arrays.
iSCSI optimization requires LLDP to be enabled. LLDP is enabled by default when an Aggregator auto-configures.
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iSCSI Optimization