Displaying And Maintaining Qos Policies - HP A5120 EI Series Configuration Manual

To do...
Apply the QoS policy globally
Applying the QoS policy to the control plane
A device provides the data plane and the control plane.
 The data plane has units responsible for receiving, transmitting, and switching (forwarding) packets,
such as various dedicated forwarding chips. They deliver super processing speeds and throughput.
The control plane has processing units running most routing and switching protocols and responsible

for protocol packet parsing 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 passes them to the control
plane. If the transmission rate exceeds the processing capability of the control plane, which may occur at
times of DoS attacks, the control plane will be busy handling undesired packets and fail to handle
legitimate packets correctly or timely.
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 action ensures that the control plane can receive, transmit,
and process packets properly.
Follow these steps to apply the QoS policy to the control plane:
To do...
Enter system view
Enter control plane view
Apply the QoS policy to the
control plane
CAUTION:

By default, some devices are configured with pre-defined control plane policies, which take effect on the control
planes by default. A pre-defined control plane QoS policy uses the system-index to identify the type of packets
sent to the control plane. You can reference system-indexes in if-match commands in class view for traffic
classification and then re-configure traffic behaviors for these classes as required. You can use the display qos
policy control-plane pre-defined command to display them.

In a QoS policy for control planes, if a system index classifier is configured, the associated traffic behavior can
contain only the CAR or accounting action. In addition, if the CAR action is configured, only its CIR setting can
be applied.

In the QoS policy for a control plane, if a system index classifier is not configured, the associated traffic
behaviors also take effect on the data traffic of the device where the control plane resides.

Displaying and maintaining QoS policies

To do...
Display traffic class configuration
Use the command...
qos apply policy policy-name
global inbound
Use the command...
system-view
control-plane slot slot-number
qos apply policy policy-name inbound
Use the command...
display traffic classifier user-defined [ tcl-name
] [ | { begin | exclude | include } regular-
expression ]
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