bum-suppression

Function

The bum-suppression command enables suppression for broadcast, unknown unicast, and multicast traffic.

The undo bum-suppression command disables suppression for broadcast, unknown unicast, and multicast traffic.

By default, suppression for broadcast, unknown unicast, and multicast traffic is not enabled.

Format

bum-suppression cir cir-value [ cbs cbs-value ] inbound

undo bum-suppression inbound

Parameters

Parameter	Description	Value
cbs cbs-value	Specifies the CBS. The CBS indicates the committed volume of traffic that an interface allows to pass and the depth of the first bucket (assuming it is bucket A).	The value is an integer ranging from 0 to 4294967295, in bytes. The default cbs-value value is equal to cir-value. If cir-value is smaller than 100000 kbit/s, the default value of cbs-value is calculated using the following formula: cir-value x (1500/8) bytes. If cir-value is greater than or equal to 100000 kbit/s, the default value of cbs-value is calculated using the following formula: 100000 x (1500/8) bytes.
inbound	Specifies the inbound direction.	-
cir cir-value	Specifies the CIR. The CIR indicates the committed rate of traffic that an interface allows to pass.	The value is an integer ranging from 0 to 4294967295, in kbit/s.

Parameter

Description

Value

cbs cbs-value

Specifies the CBS. The CBS indicates the committed volume of traffic that an interface allows to pass and the depth of the first bucket (assuming it is bucket A).

The value is an integer ranging from 0 to 4294967295, in bytes. The default cbs-value value is equal to cir-value.

If cir-value is smaller than 100000 kbit/s, the default value of cbs-value is calculated using the following formula: cir-value x (1500/8) bytes.
If cir-value is greater than or equal to 100000 kbit/s, the default value of cbs-value is calculated using the following formula: 100000 x (1500/8) bytes.

inbound

Specifies the inbound direction.

cir cir-value

Specifies the CIR. The CIR indicates the committed rate of traffic that an interface allows to pass.

The value is an integer ranging from 0 to 4294967295, in kbit/s.

Views

QoS profile view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
qos	write

Usage Guidelines

Usage Scenario

If broadcast, unknown unicast, and multicast traffic increases on networks, the traffic consumes an increasing number of network resources, which degrades network performance.

To enable suppression for broadcast, unknown unicast, and multicast traffic, run the bum-suppression command. When broadcast, unknown unicast, and multicast traffic exceeds the upper threshold, excess broadcast, unknown unicast, and multicast traffic is discarded until the traffic falls below the upper threshold.

Prerequisites

A QoS profile has been created.

Configuration Impact

For CAR and suppression: When suppression is enabled for a VSI or VLAN, Layer 2 suppression takes effect for the interface bound to the VSI or added to the VLAN. Layer 2 suppression identifies traffic types (known unicast, unknown unicast, broadcast, and multicast) and implements rate limiting based on specific configurations. When suppression is not enabled for a VSI or VLAN, Layer 2 suppression does not take effect for the interface bound to the VSI or added to the VLAN. In this case, traffic types (known unicast, unknown unicast, broadcast, and multicast) are not identified, and CAR is implemented for all traffic.

Follow-up Procedure

Apply the QoS profile in which suppression for broadcast, unknown unicast, and multicast traffic is enabled to an interface.

Precautions

The bum-suppression command takes effect only when the traffic directions specified for the bum-suppression command and the QoS profile are the same.

Example

# Enable suppression for broadcast, unknown unicast, and multicast traffic in the QoS profile named p1.

<HUAWEI> system-view
[~HUAWEI] qos-profile p1
[*HUAWEI-qos-profile-p1] bum-suppression cir 1000 inbound