H3C S6850 Series, Configuration Manual

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interface interface-type interface-number
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
About PFC
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 priority-based flow control (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.
Restrictions and guidelines
•
You can configure PFC in both system view and Ethernet interface view. If you configure PFC in
system view and Ethernet interface view multiple times, the most recent configuration takes
effect.
•
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 perform PFC on an IRF port, configure PFC on the IRF port and the IRF physical ports that
are bound to the IRF port. For information about IRF, see
IRF configuration Guide .
•
To perform PFC in an overlay network, execute the
qos trust tunnel-dot1p
command.
For information about the overlay network, see VXLAN Configuration Guide . For information
about the
qos trust tunnel-dot1p
command, see ACL and QoS Command Reference .
•
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.
•
If you configure the
flow control
or
flow-control receive enable
command on a
PFC-enabled interface, the following rules apply:
{
The PFC configuration takes effect.
{
The configuration of the
flow control
or
flow-control receive enable
command is ignored.
{
The
flow control
or
flow-control receive enable
command takes effect on the
interface only when PFC is disabled on it.
Configuring PFC in system view
1. Enter system view.
system-view
2. Enable PFC on all Ethernet interfaces.
priority-flow-control enable { receive | send }