MPLS LDP Configuration

Overview

Multiprotocol Label Switching (MPLS) Label Distribution Protocol (LDP) is widely used for transmitting virtual private network (VPN) services. MPLS LDP networking and configurations are simple. MPLS LDP supports route-driven establishment of a large number of label switched paths (LSPs).

Configuration Precautions for MPLS LDP

Configuring a Static LSP

An LSP can be established using statically configured labels.

Configuring a Local LDP Session

An MPLS LDP session can be configured only after LSR IDs are configured and MPLS LDP is enabled on both ends of the MPLS LDP session.

Configuring a Remote LDP Session

A remote MPLS LDP session can only be established after LSR IDs are configured and MPLS LDP is enabled on both ends of the MPLS LDP session.

Configuring the Dynamic LDP Advertisement Capability

On LSRs enabled with global LDP, the dynamic LDP advertisement capability allows extended LDP functions to be dynamically enabled or disabled when the LDP session is working properly, ensuring stable LSP operation.

Configuring an LDP LSP

LDP is a label distribution protocol used to establish LSPs in an MPLS domain.

Configuring LDP Extension for Inter-Area LSP

Before configuring LDP extension for inter-area LSP, familiarize yourself with the usage scenario, complete the pre-configuration tasks, and obtain the data required for the configuration.

Configuring the LDP Multi-Instance

You need to configure the LDP multi-instance when deploying the BGP/MPLS IP VPN.

Configuring IGP-based LDP Automatic Configuration

IGP-based LDP automatic configuration reduces configuration workloads and ensures correct configurations.

Configuring Static BFD to Monitor an LDP LSP

Static bidirectional forwarding detection (BFD) can be configured to detect faults in an LDP LSP.

Configuring Dynamic BFD for LDP LSPs

Dynamic bidirectional forwarding detection (BFD) for LDP LSPs is used to rapidly check LDP LSP connectivity to improve network reliability.

Configuring Dynamic BFD to Monitor an LDP Tunnel

Dynamic BFD can be configured to establish a dynamic BFD session to monitor both primary and backup LDP LSPs in an LDP tunnel. If BFD detects a fault, BFD instructs a specific LDP upper-layer application to perform a protection switchover.

Configuring LDP Bit Error Detection

LDP bit error detection enables a device to detect bit errors on LDP LSPs and trigger VPN service switchovers, which improves service reliability.

Configuring LDP Auto FRR

LDP Auto Fast Reroute (FRR) can be configured to rapidly trigger a service switchover if a fault occurs, which improves network reliability.

Configuring LDP Session Protection

LDP session protection enables a device to start the extended LDP discovery mechanism to continue to maintain an LDP session established with an LDP peer if the basic LDP discovery mechanism fails. After the basic LDP discovery mechanism recovers, the LDP protocol can rapidly converge.

Configuring LDP-IGP Synchronization

LDP-IGP synchronization helps minimize traffic interruptions when the traffic is switched from the backup link to the primary link and implement millisecond-level switchovers.

Configuring the LDP GR Helper

You can configure a device to function as a GR Helper to help a neighbor with the LDP GR process.

Configuring the LDP Entropy Label Capability

The entropy label can be used to improve load balancing in traffic forwarding.

Configuring LDP over TE

The LDP over TE function applies to the network on which core devices support TE, whereas edge devices support LDP. A TE tunnel functions as one hop of the entire LDP LSP.

Configuring LDP Security Features

LDP security features, such as MD5 authentication, keychain authentication, and the generalized TTL security mechanism (GTSM), can be configured to meet high network security requirements. By default, no LDP security features are configured. You are advised to configure security features as required to ensure system security.

Configuring an mLDP P2MP Tunnel

The mLDP P2MP LSP transmits multicast services over an IP/MPLS backbone network, which simplifies network deployment and efficiently uses network bandwidth resources.

Configuring mLDP P2MP FRR Link Protection

mLDP P2MP FRR link protection rectifies link faults on mLDP LSPs, which improves user network reliability.

Configuring Dynamic BFD to Monitor an mLDP P2MP Tunnel

Dynamic BFD can be configured to monitor a specified mLDP P2MP tunnel. If a primary tree fails, traffic can be rapidly switched to a backup tree, which reduces traffic loss.

Configuring LDP Traffic Statistics Collection

LDP traffic information on the ingress and transit nodes of an LSP can be queried only after LDP traffic statistics collection is configured.

Configuring mLDP P2MP Traffic Statistics Collection

mLDP P2MP traffic statistics collection can be enabled on the ingress, transit nodes, and but nodes on mLDP P2MP LSPs.

Configuring the Uniform/Pipe Mode for the MPLS Penultimate Hop

This section describes the process of configuring the Uniform/Pipe mode for the MPLS penultimate hop.

Maintaining MPLS LDP

MPLS LDP maintenance includes resetting LDP configurations and checking LSP connectivity.

Configuration Examples for MPLS LDP

The following sections provide configuration examples for configuring MPLS LDP.