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S e n d f e e d b a c k t o n x 5 0 0 0 - d o c f e e d b a c k @ c i s c o . c o m
1-8
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
OL-16597-01
Chapter 1 Configuring QoS
Configuring PFC and LLC
Configuring Priority Flow Control
By default, Ethernet interfaces negotiate PFC capability with the network adapter using DCBX protocol.
When PFC is enabled, PFC is applied to traffic that matches the CoS value configured for the no-drop
Ethernet class.
You can override the negotiation result by force-enabling the PFC capability. To force-enable the PFC
capability, perform this task:
Note
Priority flow control is configured on the individual member interfaces of a port channel. The PFC
configuration must be consistent across all members of the port channel for the port channel to become
operational.
The following example shows how to force-enable PFC on an interface:
switch#
configure terminal
switch(config)#
interface ethernet 1/2
switch(config-if)#
priority-flow-control mode on
To disable PFC capability for an interface, perform this task:
Configuring IEEE 802.3x Link-Level Flow Control
By default, link-level flow control capability on Ethernet interfaces is disabled. You can enable link-level
flow-control capability for the transmit and receive directions. To enable link-level flow control
capability, perform this task:
Command
Purpose
Step 1
switch#
configure terminal
Enters configuration mode.
Step 2
switch(config)#
interface
type
slot
/
port
Specifies the interface to be changed.
Step 3
switch(config-if)#
priority-flow-control
mode
{
auto
|
on
}
Sets PFC mode for the selected interface.
Specify
on
to force-enable PFC.
Specify
auto
to negotiate PFC capability.
Command
Purpose
switch(config-if)#
no priority-flow-control
mode
Disables the PFC setting for the selected
interface.
Command
Purpose
Step 1
switch#
configure terminal
Enters configuration mode.
Step 2
switch(config)#
interface
type
slot
/
port
Specifies the interface to be changed.
Step 3
switch(config-if)#
flowcontrol
[
receive
{
on
|
off
}] [
transmit
{
on
|
off
}]
Enables IEEE 802.3x link-level flow control for the
selected interface. Set
receive
and/or
transmit
on
or
off
.