mpls label advertise
Use mpls label advertise to specify the type of label the egress node will advertise to the penultimate hop.
Use undo mpls label advertise to restore the default.
Syntax
mpls label advertise { explicit-null | implicit-null | non-null }
undo mpls label advertise
Default
As egress, the device advertises an implicit null label to the penultimate hop.
Views
System view
Predefined user roles
network-admin
Parameters
explicit-null: Specifies the egress node to advertise an explicit null label of 0 to the penultimate hop.
implicit-null: Specifies the egress node to advertise an implicit null label of 3 to the penultimate hop.
non-null: Specifies the egress node to advertise a non-null label to the penultimate hop.
Usage guidelines
As a best practice, configure the egress node to advertise an implicit null label to the penultimate hop if the penultimate hop supports PHP.
If you want to simplify packet forwarding on egress but keep labels to determine QoS policies, configure the egress node to advertise an explicit null label to the penultimate hop.
Use non-null labels only in particular scenarios. For example, when OAM is configured on the egress node, the egress node can get the OAM function entity status only through non-null labels.
As a penultimate hop, the device accepts the implicit null label, explicit null label, or non-null label advertised by the egress node.
For LDP LSPs, the mpls label advertise command triggers LDP to delete the LSPs established before the command is executed and re-establishes new LSPs.
For BGP LSPs, the mpls label advertise command takes effect only on the BGP LSPs established after the command is executed. To apply the new setting to BGP LSPs established before the command is executed, delete the routes corresponding to the BGP LSPs, and then redistribute the routes.
Examples
# Configure the egress node to advertise an implicit null label to the penultimate hop.
<Sysname> system-view [Sysname] mpls label advertise implicit-null
Related commands
reset mpls ldp