Ldp Configuration Commands - Alcatel-Lucent 7450 Manual

LDP Configuration Commands

Generic Commands
ldp
Syntax [no] ldp
Context config>router
Default This command creates the context to configure an LDP parameters. LDP is not enabled by default and
must be explicitly enabled (no shutdown).
To suspend the LDP protocol, use the shutdown command. Configuration parameters are not
affected.
The no form of the command deletes the LDP protocol instance, removing all associated
configuration parameters. The LDP instance must first be disabled with the shutdown command
before being deleted.
Default
none (LDP must be explicitly enabled)
ldp-shortcut
Syntax [no] ldp-shortcut
Context config>router
Description This command enables the resolution of IGP routes using LDP LSP across all network interfaces
participating in the IS-IS and OSPF routing protocol in the system.
When LDP shortcut is enabled, LDP populates the routing table with next-hop entries corresponding
to all prefixes for which it activated an LDP FEC. For a given prefix, two route entries are populated
in the system routing table. One corresponds to the LDP shortcut next-hop and has an owner of LDP.
The other one is the regular IP next-hop. The LDP shortcut next-hop always has preference over the
regular IP next-hop for forwarding user packets and specified control packets over a given outgoing
interface to the route next-hop.
All user and specified control packets for which the longest prefix match in RTM yields the FEC
prefix will be forwarded over the LDP LSP.
When an IPv4 packet is received on an ingress network interface, a subscriber IES interface, or a
regular IES interface, the lookup of the packet by the ingress forwarding engine will result in the
packet being sent labeled with the label stack corresponding to the NHLFE of the LDP LSP when the
preferred RTM entry corresponds to an LDP shortcut.
7450 ESS MPLS Guide
Generic Commands
Page 647