mpls bfd

Function

The mpls bfd command sets the parameters of BFD sessions.

The undo mpls bfd command deletes the parameters of BFD sessions.

By default, no parameter of BFD sessions is set.

Format

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

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

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

Parameters

Parameter	Description	Value
min-tx-interval tx-interval	Specifies the interval at which BFD packets are sent.	The value ranges from 100 to 1000, in milliseconds. By default, the value is 1000. After the set service-mode enhanced command is configured on the S5720-HI, S5731-H, S5731S-H, S5730-HI, and S6720-HI, the value ranges from 3 to 1000. After the set service-mode enhanced-bfd command is configured on the S5732-H, S6730S-H, and S6730-H, the value ranges from 3 to 1000.
min-rx-interval rx-interval	Specifies the interval at which BFD packets are received.	The value ranges from 100 to 1000, in milliseconds. By default, the value is 1000. After the set service-mode enhanced command is configured on the S5720-HI, S5731-H, S5731S-H, S5730-HI, and S6720-HI, the value ranges from 3 to 1000. After the set service-mode enhanced-bfd command is configured on the S5732-H, S6730S-H, and S6730-H, the value ranges from 3 to 1000.
detect-multiplier multiplier	Specifies the local detection multiplier value of a BFD session.	An integer ranging from 3 to 50. The value is 3 by default.

Views

MPLS view

Default Level

2: Configuration level

Usage Guidelines

On an MPLS network, use BFD to detect LSP connectivity to increase the link fault detection speed. Users can change the values of BFD parameters based on actual networking. On an unstable link, if the BFD parameters are set small, the BFD session may flap. You can increase the values of BFD parameters.

Actual interval for the local device to send BFD packets = max { interval for sending BFD packets on the local end, interval for receiving BFD packets on the peer end }; actual interval for the local device to receive BFD packets = max { interval for sending BFD packets on the peer end, interval for receiving BFD packets on the local end }; and local BFD detection time = actual interval for receiving BFD packets on the local end x BFD detection multiplier on the peer end.

If no BFD packet is received from the peer device within the detection time, the link is considered as faulty and the BFD session enters the Down state. To reduce the usage of system resources, when the BFD session is detected in Down state, the system adjusts the sending interval to a random value greater than 1000 ms. When the BFD session becomes Up, the configured interval is restored.

Example

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

<HUAWEI> system-view
[HUAWEI] mpls
[HUAWEI-mpls] mpls bfd min-tx-interval 200