R21xx-HP FlexFabric 11900 MPLS Command Reference

36
Related commands
display mpls interface
mpls label advertise
Use mpls label advertise to specify the type of label the egress 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 an 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 to advertise an explicit null label of 0 to the penultimate hop.
implicit-null: Specifies the egress to advertise an implicit null label of 3 to the penultimate hop.
non-null: Specifies the egress to advertise a normal label to the penultimate hop. The value range for a
normal label is 16 to 1000000.
Usage guidelines
If the penultimate hop supports PHP, HP recommends that you configure the egress to advertise an
implicit null label to the penultimate hop. If you want to simplify packet forwarding on the egress but keep
labels in packets for the egress to determine QoS policies, you can configure the egress to advertise an
explicit null label to the penultimate hop. HP recommends not using non-null labels except in some
special scenarios. For example, when OAM is configured on the egress, the egress 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 normal label
advertised by the egress device.
The mpls label advertise command takes effect only for the LSPs established after the command is
executed. To apply the new setting to LSPs established before the command is executed, delete and then
re-establish those LSPs:
• To re-establish LDP LSPs, execute the reset mpls ldp command to reset the LDP session.
• To re-establish BGP LSPs, delete the routes corresponding to the BGP LSPs, and then redistribute the
routes.
Examples
# Configure the egress device to advertise an explicit null label to the penultimate hop.
<Sysname> system-view
[Sysname] mpls label advertise explicit-null