Configuring Priority Flow Control And Link-Level Flow Control; Configuring Link-Level Flow Control - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Configuring Priority Flow Control and Link-Level Flow Control

Configuring Priority Flow Control and Link-Level Flow Control
Cisco Nexus 5000 Series switches support priority flow control (PFC) and Link-Level Flow Control (LLC)
on Ethernet interfaces. The Ethernet interface can operate in two different modes: FCoE mode or standard
Ethernet mode.
If the interface is operating in FCoE mode, the Ethernet link is connected at the server port using a converged
network adapter (CNA).
If the interface is operating in a standard Ethernet mode, the Ethernet link is connected at the server port with
a standard Ethernet network adapter (NIC). The network adapter must support the Data Center Bridging
Exchange protocol (DCBX) for PFC or ingress policing to be supported on the interface.
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.
Procedure
Step 1
Step 2
Step 3
Step 4
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-16597-01
Command or Action
switch# configure terminal
switch(config)# interface type slot/port
switch(config-if)# priority-flow-control
mode {auto | on}
switch(config-if)# no
priority-flow-control mode on
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
Configuring Priority Flow Control
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.
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