Iscsi Concepts - NETGEAR ProSAFE M5300 Series Software Administration Manual

Managed Switches

iSCSI Concepts

The Internal Small Computer System Interface (iSCSI) feature is used in networks containing
iSCSI initiators and targets where the administrator desires to protect the iSCSI traffic from
interruption by giving the traffic preferential QoS treatment. The dynamically generated
classifier rules are used to direct the iSCSI data traffic to queues that can be given the
desired preference characteristics over other data transiting the switch. This can avoid
session interruptions during times of congestion that would otherwise cause iSCSI packets to
be dropped.
The administrator can select VLAN priority tag (VPT) or DSCP mapping for the QoS
preferential treatment. iSCSI flows are assigned by default to the highest VPT/DSCP queue
not used for chassis management or voice VLAN. The administrator should also take care
of configuring the relevant Class of Service parameters for the queue chosen in order to
complete the setting.
The following figure shows an example of iSCSI implementation.
Figure 63. Sample iSCSI implementation
iSCSI
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