Priority-Based Flow Control (Pfc); Internet Small Computer System Interface (Iscsi) Optimization - Dell PowerEdge M420 Configuration Manual

Priority-based Flow Control (PFC)

NOTE:
PFC is supported only on the PCM8024-k. The PCM6220, PCM6348, and
PCM8024 switches do not support PFC.
The Priority-based Flow Control feature allows the user to pause or inhibit
transmission of individual priorities within a single physical link. By
configuring PFC to pause a congested priority (priorities) independently,
protocols that are highly loss sensitive can share the same link with traffic that
has different loss tolerances. Priorities are differentiated by the priority field
of the 802.1Q VLAN header.
NOTE:
An interface that is configured for PFC is automatically disabled for 802.3x
flow control.
For information about configuring the PFC feature, see "Configuring Port-
Based Traffic Control" on page 691.

Internet Small Computer System Interface (iSCSI) Optimization

NOTE:
iSCSI is supported on the PCM6348, PCM8024, and PCM8024-k switches.
The M6220 switch does not support iSCSI.
The iSCSI Optimization feature helps give traffic between iSCSI initiator
and target systems special QoS treatment in the switch. This is accomplished
by monitoring, or snooping traffic to detect packets used by iSCSI stations in
establishing iSCSI sessions and connections. Data from these exchanges is
used to create classification rules to assign the traffic between the stations to
a configured traffic class. This affects how the packets in the flow are queued
and scheduled for egress on the destination port.
For information about configuring iSCSI settings, see "Configuring iSCSI
Optimization" on page 439.
Switch Features
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