notify neighbor-down

Function

The notify neighbor-down command configures a BFD session to notify the upper layer protocol when the BFD session detects a neighbor Down event.

The undo notify neighbor-down command restores the default configuration.

By default, when the BFD detection time expires or a BFD session detects a neighbor Down event, the BFD session notifies the upper layer protocol.

Format

notify neighbor-down

undo notify neighbor-down

Parameters

None

Views

BFD-LSP session view

Default Level

2: Configuration level

Usage Guidelines

In most cases, when you use a BFD session to detect link faults, the BFD session notifies the upper layer protocol of a link fault in the following scenarios:

When the BFD detection time expires, the BFD session notifies the upper layer protocol. BFD sessions must be configured on both ends. If the BFD session on the local end does not receive any BFD packets from the remote end within the detection time, the BFD session on the local end concludes that the link fails and notifies the upper layer protocol of the link fault.
When a BFD session detects a neighbor Down event, the BFD session notifies the upper layer protocol. If the BFD session on the local end detects a neighbor Down event within the detection time, the BFD session on the local end directly notifies the upper layer protocol of the neighbor Down event.

When you use a BFD session to detect faults on an LSP, you need only be concerned about whether a fault occurs on the link from the local end to remote end. In this situation, run the notify neighbor-down command to configure the BFD session to notify the upper layer protocol only when the BFD session detects a neighbor Down event. This configuration prevents the BFD session from notifying the upper layer protocol when the BFD detection time expires and ensures that services are not interrupted.

Example

# Configure the BFD session to notify the upper layer protocol when the BFD session detects a neighbor Down event.

<HUAWEI> system-view
[HUAWEI] bfd atob bind ldp-lsp peer-ip 10.1.2.1 nexthop 10.1.1.2 interface vlanif 100
[HUAWEI-bfd-lsp-session-atob] discriminator local 1
[HUAWEI-bfd-lsp-session-atob] discriminator remote 2
[HUAWEI-bfd-lsp-session-atob] notify neighbor-down
[HUAWEI-bfd-lsp-session-atob] commit