Setting Pfc Thresholds - H3C S6850 Series Configuration Manual

By default, PFC is disabled on all Ethernet interfaces.
3. Enable PFC for 802.1p priorities on all Ethernet interfaces.
priority-flow-control no-drop dot1p dot1p-list
By default, PFC is disabled for all 802.1p priorities on all Ethernet interfaces.
Configuring PFC in Ethernet interface view
1. Enter system view.
system-view
2. Enter Ethernet interface view.
interface interface-type interface-number
3. Enable PFC on the Ethernet interface.
priority-flow-control enable { receive | send }
By default, PFC is disabled on an Ethernet interface.
4. Enable PFC for 802.1p priorities.
priority-flow-control no-drop dot1p dot1p-list
By default, PFC is disabled for all 802.1p priorities.
5. (Optional.) Set the pause time in PFC pause frames.
priority-flow-control pause-time time-vale
By default, the pause time in PFC pause frames is 65535.

Setting PFC thresholds

About PFC thresholds
The storage spaces for an interface include the following types:
•
Headroom storage space.
•
Shared storage space.
•
Guaranteed storage space.
Setting PFC thresholds enables flexible control over PFC and can make good use of the storage
spaces. The device supports the following PFC thresholds:
•
Headroom buffer threshold—Maximum number of cell resources that can be used by packets
with a specific 802.1p priority value in a headroom storage space. An interface drops received
packets once this threshold is reached.
•
Back pressure frame triggering threshold—Maximum number of cell resources that can be
used by packets with a specific 802.1p priority value in a shared storage space. PFC is
triggered once this threshold is reached. The back pressure frame triggering threshold includes
the following types:
Dynamic back pressure frame triggering threshold—Maximum cell resources set in
percentage.
Static back pressure frame triggering threshold—Maximum cell resources set in an
absolute value.
•
Offset between the back pressure frame stopping threshold and triggering
threshold—When the number of cell resources used by packets with a specific 802.1p priority
value decreases by this offset after PFC is triggered, PFC will be stopped.
•
PFC reserved threshold—Number of cell resources reserved for packets with a specific
802.1p priority value in a guaranteed storage space.
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