LDP Configuration

LDP Configuration Hierarchy

The diagram below illustrates the LDP configuration hierarchy.

LDP Configuration Hierarchy
Figure 1. LDP Configuration Hierarchy

Configuration Syntax and Commands

The following sections describe the LDP configuration syntax and commands.

LDP Instance Configuration

At this configuration hierarchy, you configure LDP protocol parameters which are generic to the LDP instance.

Syntax:

set instance <instance-name> protocol ldp <attribute> <value>

Attribute Description

<instance-name>

Name of the LDP instance.

interface <name>

Name of the logical interface.

router-id <router-id>

Router identifier in IPv4 format.

address-family <afi>

Address family identifier (AFI). Supported values: ipv4, or ipv6. Refer to section LDP Address Family Configuration for LDP address family configuration details.

connection-preference <afi>

Specifies the connection preference for the TCP session. Supported values: ipv4, or ipv6. By default, IPv6 is used as the preferred TCP connection if an IPv6 source address is configured. Refer to section Dual-stack LDP for more information on the LDP Dual-stack behaviour.

igp-synchronization <…​>

LDP IGP synchronization configuration. This option is supported only on interfaces running Intermediate System-to-System (IS-IS) or OSPFv2 processes. Refer to section LDP IGP Synchronization for LDP-IGP synchronization configuration details.

source-address <ipv4|ipv6> <source-address>

Use the specified IP addresses (IPv4 or IPv6) as the transport address for the LDP session. For LDP over IPv6, the IPv6 source address is mandatory. Refer to section Dual-stack LDP for more information on the LDP Dual-stack behavior.

loop-detection <…​>

The LDP loop detection feature enables LDP to detect loops during an LSP establishment. Refer to section LDP Loop Detection Configuration for the loop detection configuration details.

protocol-preference (internal | external) <preference-value>

Specifies the protocol preference of routes learned by T-LDP ('external'), LDP ('internal'), or both. This preference is used to select routes learned from multiple protocols.

external: Range: 1 to 255. Default: 190. internal: Range: 1 to 255. Default: 9.

timer <…​>

Specifies the Hello hold time, Hello interval, Keepalive hold time, and Keepalive interval. Refer to section LDP Timer Configuration for the LDP timer configuration details.

session <ipv4|ipv6> <address> `authentication-id <…​>

Specifies an IPv4 or IPv6 LDP session attributes to apply TCP authentication. Refer to section LDP Authentication Configuration.

targeted-neighbor <ipv4|ipv6> <neighbor-address> <source-address>

Specifies the IPv4 or IPv6 address of the targeted LDP neighbor. Refer to section LDP Targeted Neighbor Configuration.

session <ipv4|ipv6> <address> export-policy|import-policy <…​>

Specifies an IPv4 or IPv6 LDP session attributes to apply import/export policy configurations. Refer to section LDP Import and Export Policy Configuration.

Example: LDP Instance Configuration

This following configuration example sets the LDP router ID and enables LDP on various interfaces for the default instance.

set instance default protocol ldp router-id 198.51.100.1
set instance default protocol ldp interface ifl-0/0/0/1
set instance default protocol ldp interface ifl-0/0/0/100
set instance default protocol ldp interface ifl-0/0/0/101
set instance default protocol ldp interface ifl-0/0/1/102
set instance default protocol ldp interface ifl-0/0/2/1
set instance default protocol ldp interface ifl-0/0/3/1
set instance default protocol ldp interface lo-0/0/0/1
set instance default protocol ldp interface lo-0/0/0/2
set instance default protocol ldp interface lo-0/0/0/3
set instance default protocol ldp interface lo-0/0/0/4
set instance default protocol ldp interface lo-0/0/0/5
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp
{
    "rtbrick-config:ldp": {
      "router-id": "198.51.100.1",
      "interface": [
        {
          "name": "ifl-0/0/0/1"
        },
        {
          "name": "ifl-0/0/0/100"
        },
        {
          "name": "ifl-0/0/0/101"
        },
        {
          "name": "ifl-0/0/1/102"
        },
        {
          "name": "ifl-0/0/2/1"
        },
        {
          "name": "ifl-0/0/3/1"
        },
        {
          "name": "lo-0/0/0/1"
        },
        {
          "name": "lo-0/0/0/2"
        },
        {
          "name": "lo-0/0/0/3"
        },
        {
          "name": "lo-0/0/0/4"
        },
        {
          "name": "lo-0/0/0/5"
        }
      ]
    }
  }

The following configuration example sets the administrative preference values for external and internal LDP routes within the default instance.

set instance default protocol ldp protocol-preference external 150
set instance default protocol ldp protocol-preference internal 8
commit
supervisor@rtbrick>LEAF01: cfg> show config instance default protocol ldp protocol-preference
{
  "rtbrick-config:protocol-preference": {
    "external": 150,
    "internal": 8
  }
}

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP Targeted Neighbor Configuration

The targeted neighbor configuration establishes an LDP neighbor with a remote neighbor that is not directly connected.

Syntax:

set instance <instance> protocol ldp targeted-neighbor <attribute> <value>

Attribute Description

ipv4 <neighbor-address>

IPv4 address of the remote LDP neighbor.

ipv4 <neighbor-address> <source-address>

Neighbhor address to which ldp hello is sent

ipv4 <neighbor-address> <source-address> hold-time <hold-time>

Targeted hold time, <0-65535>, default 45s

ipv4 <neighbor-address> <source-address> interval <interval>

Targeted hello messages interval, <0-65535>, default 15s

ipv4 <neighbor-address> <source-address> neighbor-type <receiver |sender>

Specifies the neighbor type, that is, sender or receiver.

ipv6 <neighbor-address>

IPv6 address of the remote LDP neighbor.

ipv6 <neighbor-address> <source-address>

Neighbhor address to which ldp hello is sent

ipv6 <neighbor-address> <source-address> hold-time <hold-time>

Targeted hold time, <0-65535>, default 45s

ipv6 <neighbor-address> <source-address> interval <interval>

Targeted hello messages interval, <0-65535>, default 15s

ipv6 <neighbor-address> <source-address> neighbor-type <receiver |sender>

Specifies the neighbor type, that is, sender or receiver.

The following example configurates the targeted LDP neighbors for both IPv4 and IPv6 addresses within the default instance.

set instance default protocol ldp targeted-neighbor ipv4 neighbor-address 198.51.100.1 source-address 198.51.100.2
set instance default protocol ldp targeted-neighbor ipv4 neighbor-address 198.51.100.5 source-address 198.51.100.2
set instance default protocol ldp targeted-neighbor ipv6 neighbor-address 2001:DB8::1 source-address 2001:DB8::2
set instance default protocol ldp targeted-neighbor ipv6 neighbor-address 2001:DB8::5 source-address 2001:DB8::2
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp targeted-neighbor
{
  "rtbrick-config:targeted-neighbor": {
    "ipv4": [
      {
        "neighbor-address": "198.51.100.1",
        "source-address": "198.51.100.2"
      },
      {
        "neighbor-address": "198.51.100.5",
        "source-address": "198.51.100.2"
      }
    ],
    "ipv6": [
      {
        "neighbor-address": "2001:DB8::1",
        "source-address": "2001:DB8::2"
      },
      {
        "neighbor-address": "2001:DB8::5",
        "source-address": "2001:DB8::2"
      }
    ]
  }
}

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP Address Family Configuration

The address-family command allows you to enable the address families that LDP will route and configure settings that are specific to that address family.

Syntax:

set instance <instance-name> protocol ldp address-family <attribute> <value>

Attribute Description

<afi>

Address family identifier (AFI). Supported AFI values: ipv4, ipv6.

<safi>

Subsequent address family identifier (SAFI). Supported SAFI value: labeled-unicast.

Configuring SAFI is now mandatory during the redistribution configuration or when enabling/disabling status.

<afi> <safi> status <enable|disable>

Enable or disable address family. By default, both IPv4 and IPv6 address families are enabled, as LDP supports dual stack. Refer to section Dual-stack LDP for more information on the LDP Dual-stack behavior.

<afi> <safi> redistribute <source>

Specifies the source from which the routes are to be redistributed. The available options include direct, ipoe, isis, ospf, ppp, and static.

<afi> <safi> redistribute <source> policy <policy>

Specifies the name of the policy map. The redistribute attach point allows routes from other sources to be advertised by LDP. The policy can be applied only to the routes that are redistributed from other sources to LDP.

Example 1: LDP Address Family Configuration

set instance default protocol ldp address-family ipv6 labeled-unicast status enable
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp address-family
{
  "rtbrick-config:address-family": [
    {
      "afi": "ipv6",
      "safi": "labeled-unicast",
      "status": "enable"
    }
  ]
}

Example 2: LDP Redistribution Configuration

set instance default protocol ldp address-family ipv4 redistribute direct
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp address-family ipv4 redistribute direct
{
  "rtbrick-config:redistribute": [
    {
      "source": "direct"
    }
  ]
}

Example 3: LDP Policy Configuration

set instance default protocol ldp address-family ipv4 redistribute direct policy filter-link-address
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp address-family ipv4 redistribute
{
  "rtbrick-config:redistribute": [
    {
      "source": "direct",
      "policy": "filter-link-address"
    }
  ]
}

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP Loop Detection Configuration

The LDP loop detection feature enables LDP to detect loops during an LSP establishment.

Syntax:

set instance <instance-name> protocol ldp loop-detection <attribute> <value>

Attribute Description

hop-count <hop-count>

Specifies the hop count limit for loop detection. Range: 0-255. Default: 32.

status <enable|disable>

Enables or disables loop detection. By default, this option is disabled. When this option is enabled, both hop count and path vector are enabled.

vector-length <vector-length>

Specifies the path vector length limit for loop detection. Range: 0-255. Default: 32.

Example 1: LDP Loop Detection Configuration

set instance default protocol ldp loop-detection enable true
set instance default protocol ldp loop-detection hop-count 64
set instance default protocol ldp loop-detection vector-length 64
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp loop-detection
{
    "rtbrick-config:loop-detection": {
      "enable": "true",
      "hop-count": 64,
      "vector-length": 64
    }
  }

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP Timer Configuration

Specify the hello timer and hold-down timer for LDP adjacency. Similarly, specify the keepalive and keepalive timeout settings for the LDP session.

Syntax:

set instance <instance-name> protocol ldp timer <attribute> <value>

Attribute Description

hello hold-time <hold-time>

Specifies the hello hold-time interval in seconds before declaring a neighbor to be down. Range: 0-65535. Default: 15.

hello interval <interval>

Specifies the hello messages interval in seconds. Range: 0-65535. Default: 5.

session keepalive-interval <keepalive-interval>

Specifies the session keepalive messages interval in seconds. Range: 1-65535. Default: 10.

session keepalive-timeout <keepalive-timeout>

Specifies the session keepalive timeout in seconds before declaring a session to be down. Range: 1-65535. Default: 30.

Example 1: LDP Timer Configuration

set instance default protocol ldp timer hello interval 10
set instance default protocol ldp timer hello hold-time 20
set instance default protocol ldp timer session keepalive-interval 3000
set instance default protocol ldp timer session keepalive-timeout 5000
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp timer
{
    "rtbrick-config:timer": {
      "hello": {
        "interval": 10,
        "hold-time": 20
      },
      "session": {
        "keepalive-interval": 3000,
        "keepalive-timeout": 5000
      }
    }
  }

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP IGP Synchronization

Synchronization between LDP and the underlying interior gateway protocol (IGP) ensures that the LDP path is fully established before the IGP path is used for forwarding traffic. LDP IGP synchronization is supported only on interfaces running Intermediate System-to-System (IS-IS) or OSPFv2 processes.

Syntax:

set instance <instance-name> protocol ldp igp-synchronization <attribute> <value>

Attribute Description

hold-timer <hold-timer>

Specifies the hold-timer in seconds to limit how long the IGP session must wait before declaring the LDP synchronization. Range: 0-60. Default: 10.

Example 1: LDP IGP Synchronization Configuration

set instance default protocol ldp igp-synchronization hold-timer 60
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp igp-synchronization
{
    "rtbrick-config:igp-synchronization": {
     hold-timer": 60,
    }
  }

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP Authentication Configuration

To meet the security requirements of LDP sessions, configure LDP authentication.

Syntax:

set instance <instance-name> protocol ldp session ipv4|ipv6 <address> authentication-id <authentication-id>

Attribute Description

<address>

Specifies the transport IP address of the peer.

<authentication-id>

Authentication Tuple Identifier

Example 1: LDP Authentication Configuration

set instance default protocol ldp session ipv4 address 198.51.100.2 authentication-id auth_id_1
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp session ipv4
{
  "rtbrick-config:ipv4": [
    {
      "address": "198.51.100.2",
      "authentication-id": "auth_id_1"
    }
  ]
}

api  To access the RESTCONF API that corresponds to this CLI, click here.

TCP Authentication Configuration

In the instance TCP authentication hierarchy, you can optionally enable MD5 or HMAC-SHA-1-96, HMAC-SHA-256-128, or AES-128-CMAC-96 authentication. Authentication is not configured for LDP directly, but for the TCP sessions used by LDP.

Syntax:

set instance <instance> tcp authentication <authentication-id> <attribute> <value>

Attribute Description

<authentication-id>

Authentication identifier

type <type>

Authentication identifier such as MD5 or HMAC-SHA-1-96,HMAC-SHA-256-128 or AES-128-CMAC-96

key1-id <key1-id>

Key ID1 of the receiver

key1-encrypted-text <key1-encrypted-text>

Encrypted text of key1

key1-plain-text <key1-plain-text>

Plain text of key1

key2-id <key2-id>

Key ID2 of the receiver

key2-encrypted-text <key2-encrypted-text>

Encrypted text of key2

key2-plain-text <key2-plain-text>

Plain text of key2

Example: LDP TCP Authentication Configuration

set instance default tcp authentication auth_id_1 type MD5
set instance default tcp authentication auth_id_1 key1-id 1
set instance default tcp authentication auth_id_1 key1-encrypted-text "$2a6fd7db50a18a9f1f16b5c5b4214fab0"
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default tcp authentication auth_id_1
{
  "rtbrick-config:authentication": [
    {
      "authentication-id": "auth_id_1",
      "type": "MD5",
      "key1-id": 1,
      "key1-encrypted-text": "$2a6fd7db50a18a9f1f16b5c5b4214fab0"
    }
  ]
}

api  To access the RESTCONF API that corresponds to this CLI, click here.

LDP Import and Export Policy Configuration

Syntax:

set instance <instance-name> protocol ldp session ipv4|ipv6 <address> <attribute> <value>

Attribute Description

<address>

Specifies the IPv4 or IPv6 address.

export-policy <export-policy>

Export policy identifier

import-policy <import-policy>

Import policy identifier

Example 1: LDP Export Configuration

set instance default protocol ldp session ipv4 address 198.51.100.2 export-policy exp-policy1
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp session ipv4
{
  "rtbrick-config:ipv4": [
    {
      "address": "198.51.100.2",
      "export-policy": "exp-policy1"
    }
  ]
}

Example 3: LDP Import Configuration

set instance default protocol ldp session ipv4 address 198.51.100.2 import-policy imp-policy1
commit
supervisor@rtbrick>SPINE01: cfg> show config instance default protocol ldp session ipv4
{
  "rtbrick-config:ipv4": [
    {
      "address": "198.51.100.2",
      "import-policy": "imp-policy1"
    }
  ]
}

api  To access the RESTCONF API that corresponds to this CLI, click here.