Configuring Priority Flow Control; Configuring Link-Level Flow Control - Cisco Nexus 5000 Series Configuration Manual

Configuring QoS
You must configure a system class with the pause no-drop parameter for PFC to operate on Ethernet traffic
Note
(PFC will be applied to traffic that matches the CoS value configured for this class).

Configuring Priority Flow Control

By default, Ethernet interfaces negotiate PFC with the network adapter using the DCBX protocol. When PFC
is enabled, PFC is applied to traffic that matches the CoS value configured for the no-drop class.
You can override the negotiation result by forcing the interface to enable PFC.
SUMMARY STEPS
1. switch# configure terminal
2. switch(config)# interface type slot/port
3. switch(config-if)# priority-flow-control mode {auto | on}
4. (Optional) switch(config-if)# no priority-flow-control mode on
DETAILED STEPS
Command or Action
Step 1 switch# configure terminal
Step 2 switch(config)# interface type slot/port
Step 3 switch(config-if)# priority-flow-control mode
{auto | on}
Step 4 switch(config-if)# no priority-flow-control mode
on
This 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

Configuring Link-Level Flow Control

By default, LLC on Ethernet interfaces is disabled. You can enable LLC for the transmit and receive directions.
OL-20921-01
Purpose
Enters configuration mode.
Specifies the interface to be changed.
Sets PFC mode for the selected interface.
Specifies auto to negotiate PFC capability. This is the default.
Specifies on to force-enable PFC.
(Optional)
Disables the PFC setting for the selected interface.
Cisco Nexus 5000 Series NX-OS Quality of Service Configuration Guide
Configuring Priority Flow Control
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