mpls bgp bfd (MPLS-BGP-VPN instance view)

Function

The mpls bgp bfd command sets time parameters for BGP BFD sessions.

The undo mpls bgp bfd command restores default time parameters for BGP BFD sessions.

By default, no time parameters are set for BGP BFD sessions.

Format

mpls bgp bfd { detect-multiplier value-detect-multiplier | min-rx-interval value-min-rx-interval | min-tx-interval value-min-tx-interval } ^*

undo mpls bgp bfd { detect-multiplier value-detect-multiplier | min-rx-interval value-min-rx-interval | min-tx-interval value-min-tx-interval } ^*

undo mpls bgp bfd { detect-multiplier | min-rx-interval | min-tx-interval } ^*

Parameters

Parameter	Description	Value
detect-multiplier value-detect-multiplier	Specifies the local BGP BFD detection multiplier.	The value is an integer ranging from 3 to 50. The default value is 3.
min-rx-interval value-min-rx-interval	Specifies the minimum interval at which BGP BFD packets are received.	The value is an integer ranging from 3 to 20000, in milliseconds. The default value is 10.
min-tx-interval value-min-tx-interval	Specifies the minimum interval at which BGP BFD packets are sent.	The value is an integer ranging from 3 to 20000, in milliseconds. The default value is 10.

Parameter

Description

Value

detect-multiplier value-detect-multiplier

Specifies the local BGP BFD detection multiplier.

The value is an integer ranging from 3 to 50. The default value is 3.

min-rx-interval value-min-rx-interval

Specifies the minimum interval at which BGP BFD packets are received.

The value is an integer ranging from 3 to 20000, in milliseconds. The default value is 10.

min-tx-interval value-min-tx-interval

Specifies the minimum interval at which BGP BFD packets are sent.

The value is an integer ranging from 3 to 20000, in milliseconds. The default value is 10.

Views

MPLS-BGP-VPN instance view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bgp	write

Usage Guidelines

Usage Scenario

A BGP BFD session working in asynchronous mode monitors BGP LSPs over BGP tunnels. The ingress and egress of E2E BGP LSPs exchange BFD packets periodically. If a node receives no BFD packet after the detection period elapses, the node considers the BGP LSP faulty.

BFD time parameters are calculated as follows:

Effective local interval at which BFD packets are sent = MAX { Locally configured minimum interval at which BFD packets are sent, Remotely configured minimum interval at which BFD packets are received }
Effective local interval at which BFD packets are received = MAX { Remotely configured minimum interval at which BFD packets are sent, Locally configured minimum interval at which BFD packets are received }
Local BFD detection period = Effective local interval at which BFD packets are received x Remotely configured BFD detection multiplier
The egress has the fixed minimum interval at which BGP BFD packets are sent, the fixed minimum interval at which BGP BFD packets are received, and the detection multiplier of 3. You can only change the time parameters on the ingress so that the BFD time parameters can be updated on both the ingress and egress.

Example

# Set the minimum interval at which BGP BFD packets are sent to 200 ms.

<HUAWEI> system-view
[~HUAWEI] ip vpn-instance vpna
[*HUAWEI-vpn-instance-vpna] quit
[*HUAWEI] mpls
[*HUAWEI-mpls] quit
[*HUAWEI] bfd
[*HUAWEI-bfd] quit
[*HUAWEI] mpls bgp vpn-instance vpna
[*HUAWEI-mpls-bgp-vpn-instance-vpna] mpls bgp bfd min-tx-interval 200