peer label-route-capability (BGP-IPv4 unicast address family view)

Function

The peer label-route-capability command enables a BGP device to exchange labeled routes with a specified peer.

The undo peer label-route-capability command disables this function.

By default, this function is disabled.

Format

peer ipv4-address label-route-capability [ check-tunnel-reachable ]

undo peer ipv4-address label-route-capability

Parameters

Parameter	Description	Value
ipv4-address	Specifies the IPv4 address of a peer.	It is in dotted decimal notation.
check-tunnel-reachable	Checks tunnel reachability when imported routes are sent as labeled routes.	-

Parameter

Description

Value

ipv4-address

Specifies the IPv4 address of a peer.

It is in dotted decimal notation.

check-tunnel-reachable

Checks tunnel reachability when imported routes are sent as labeled routes.

Views

BGP-IPv4 unicast address family view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bgp	write

Usage Guidelines

Usage Scenario

The peer label-route-capability command is applicable to the scenario where labeled IPv4 routes need to be exchanged between the local end and the specified peer.

Configuring the check-tunnel-reachable parameter can only be used to check tunnels on IPv4 public networks.

If the check-tunnel-reachable parameter is configured, BGP advertises IPv4 unicast routes to peers when routed tunnels are unreachable or advertises labeled routes to peers when routed tunnels are reachable. In VPN scenario, this eliminates the risk of establishing an MP-EBGP peer relationship between PEs over a faulty LSP because this will cause data forwarding failures.
If the check-tunnel-reachable parameter is not configured, BGP advertises labeled routes to peers whether the tunnels for imported routes are reachable or not.
NOTE:
To disable tunnel reachability checking, run the peer label-route-capability command, not the undo peer label-route-capability command.

Prerequisites

The peer as-number command has been run to create a peer.

Configuration Impact

If the peer label-route-capability command is run multiple times, the latest configuration overwrites the previous one.

Precautions

When the capability of sending labeled routes is enabled or disabled, BGP connection is automatically closed and the capability of the neighbor is re-negotiated, and then the BGP connection is automatically established.

If the peer label-route-capability command is run in the IPv4 unicast address family view to enable the device to send labeled routes to a specified peer, the function takes effect only after the apply mpls-label command is run in the view of the export route-policy that is applied to routes to be sent to the peer.

To configure a 6PE device to send labeled routes, specify an IPv4 unicast address for the peer of the device in the IPv6 unicast address family view.

Example

# Enable BGP to send labeled routes, and enable tunnel reachability checking.

<HUAWEI> system-view
[~HUAWEI] bgp 100
[*HUAWEI-bgp] peer 10.1.1.2 as-number 100
[*HUAWEI-bgp] ipv4-family unicast
[*HUAWEI-bgp-af-ipv4] peer 10.1.1.2 label-route-capability check-tunnel-reachable

# Enable BGP to send the labeled routes.

<HUAWEI> system-view
[~HUAWEI] bgp 100
[*HUAWEI-bgp] peer 10.1.1.2 as-number 100
[*HUAWEI-bgp] ipv4-family unicast
[*HUAWEI-bgp-af-ipv4] peer 10.1.1.2 label-route-capability