9
To enable generic flow control on an Ethernet interface:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter Ethernet interface
view.
interface interface-type
interface-number
N/A
3.
Enable generic flow
control.
•
Enable
TxRx-mode
generic flow control:
flow-control
•
Enable Rx-mode generic
flow control:
flow-control receive
enable
By default, generic flow control is
disabled on an Ethernet interface.
Configuring PFC on an Ethernet interface
When congestion occurs in the network, the local device notifies the peer to stop sending packets
carrying the specified 802.1p priority if all of the following conditions exist:
•
Both the local end and the remote end have PFC enabled.
•
Both the local end and the remote end have the
priority-flow-control no-drop dot1p
command configured.
•
The specified 802.1p priority is in the 802.1p priority list specified by the
dot1p-list
argument.
•
The local end receives a packet carrying the specified 802.1p priority.
The state of the PFC feature is determined by the PFC configuration on the local end and on the peer
end. In
:
•
The first row lists the PFC configuration on the local interface.
•
The first column lists the PFC configuration on the peer.
•
The
Enabled
and
Disabled
fields in other cells are possible negotiation results.
Make sure all interfaces that a data flow passes through have the same PFC configuration.
Table 1 PFC configurations and negotiation results
Local (right)
Peer (below)
enable auto
Default
enable
Enabled Enabled.
Disabled
auto
Enabled
•
Enabled if negotiation
succeeds.
•
Disabled if negotiation fails.
Disabled
Default
Disabled Disabled.
Disabled
Configuration restrictions and guidelines
When you configure PFC, follow these restrictions and guidelines:
•
For IRF and other protocols to operate correctly, as a best practice, do not enable PFC for
802.1p priorities 0, 6, and 7.
•
To avoid packet loss, apply the same PFC configuration to all interfaces that the packets pass
through.
•
If you do not enable PFC on an interface, the interface can receive but cannot process PFC
pause frames. To make PFC take effect, you must enable PFC on both ends.