H3C Technologies H3C S6300 Series Switches - Manual (Page 31)

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Step Command Remarks
1. Enter system view. system-view N/A
2. Apply the QoS policy
globally.
qos apply policy policy-name global
{ inbound | outbound } By default, no QoS policy is applied
globally.
Applying the QoS policy to the control plane
A device provides the data plane and the control plane.
• The units at the data plane are responsible for receiving, transmitting, and switching (forwarding)
packets, such as various dedicated forwarding chips. They deliver super processing speeds and
throughput.
• The units at the control plane are processing units running most routing and switching protocols and
responsible for protocol packet resolution and calculation, such as CPUs. Compared with data
plane units, the control plane units allow for great packet processing flexibility but have lower
throughput.
When the data plane receives packets that it cannot recognize or process, it transmits them to the control
plane. If the transmission rate exceeds the processing capability of the control plane, the control plane
will be busy handling undesired packets and fail to handle legitimate packets correctly or timely. As a
result, protocol performance is affected.
To address this problem, apply a QoS policy to the control plane to take QoS actions, such as traffic
filtering or rate limiting, on inbound traffic. This makes sure the control plane can correctly receive,
transmit, and process packets.
By default, the switch is configured with pre-defined control plane QoS policies, which take effect on the
control planes by default. A pre-defined control plane QoS policy uses the protocol type or protocol
group type to identify the type of packets sent to the control plane. You can reference protocol types or
protocol group types in if-match commands in traffic class view for traffic classification and then
re-configure traffic behaviors for these traffic classes as required. You can use the display qos policy
control-plane pre-defined command to display them.
Configuration guidelines
If a QoS policy applied to the control plane uses if-match control-plane protocol-group or if-match
control-plane protocol for traffic classification in a class, the action in the associated traffic behavior can
only be car or the combination of car and accounting packet, and only the cir keyword in the car action
can be applied normally.
Configuration procedure
To apply the QoS policy to the control plane:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter control plane view. control-plane slot slot-number N/A
3. Apply the QoS policy to
the control plane.
qos apply policy policy-name inbound
By default, no QoS policy
is applied to a control
plane.