# MPLS-LDP Configuration Mode Commands

The MPLS-LDP Configuration Mode is used to configure Label Distribution Protocol (LDP) specific parameters for MPLS-IP forwarding.

IMPORTANT:

The commands or keywords/variables that are available are dependent on platform type, product version, and installed license(s).
advertise-labels

Configures the Label Advertisement parameters.
Platform:

ASR 5000
Product:

GGSN, P-GW, SAEGW
Privilege:

Security Administrator, Administrator
Syntax

    [ no ] advertise-labels { explicit-null | implicit-null }

    default advertise-labels

no

Disables the label advertisement parameters.
default

Advertises the labels from the label space allocated for LDP protocol.
explicit-null

Advertises the Explicit NULL label for all the prefixes.
implicit-null

Advertises the Implicit NULL label for all the prefixes.
Usage:

Use this to configure advertisement of the Implicit NULL or Explicit NULL label for all the prefixes advertised by the system in this context.
Example:
The following command configures the MPLS-IP forwarding to advertise the Explicit NULL label for all the prefixes:

    advertise-labels explicit-null

The following command configures the MPLS-IP forwarding to advertise the Implicit NULL label for all the prefixes:

    advertise-labels implicit-null

discovery

Configures the Label Distribution Protocol (LDP) neighbor discovery parameters.
Platform:

ASR 5000
Product:

GGSN, P-GW, SAEGW
Privilege:

Security Administrator, Administrator
Syntax

    discovery { hello { hello-interval integer_value | hold-interval integer_value } | transport-address ipv4_addr }

    default discovery hello

    no discovery transport-address

default

Sets the LDP discovery hello interval at 5 seconds and hold interval at 15 seconds.
no

Disables the LDP neighbor discovery.
hello { hello-interval integer_value | hold-interval integer_value }

Configures the LDP Hello parameters.

hello-interval configures the frequency of sending the Discovery Hello packets in seconds.

integer_value is an integer from 5 through 21845.

Default: 5

hold-interval configures the Discovery Hold time interval in seconds.

integer_value is an integer from 15 through 65535.

Default: 15
transport-address ipv4_addr

Configures the LDP transport address as an IPv4 address entered in dotted-decimal notation. Transport address is the same as the LDP router ID.
Usage:

This is an optional command that is used to configure LDP peer discovery parameters. The LDP discovery hold-interval is always set to three times the LDP discovery hello-interval. Transport address is the address used for the TCP session over which LDP is running. If the transport address is not configured, the LDP router-id is used as transport address. Any update to transport address will take effect only if LDP is disabled and re-enabled. The “default” option sets the hello intervals to the default values.
Example:
The following command sequence configures the LDP peer discovery parameters:

    discovery hello hello-interval
    10discovery hello hold-interval
    30discovery transport-address
    10.2.3.4

enable

Enables the Label Distribution Protocol (LDP).
Platform:

ASR 5000
Product:

GGSN, P-GW, SAEGW
Privilege:

Security Administrator, Administrator
Syntax

    [ no ] enable

no

Disables the LDP protocol.
Usage:

This command is used to enable or disable the LDP protocol. By default the LDP protocol is disabled.
Example:
Use the following command to enable the LDP protocol:

    enable

end

Exits the current configuration mode and returns to the Exec mode.
Product:

All
Privilege:

Security Administrator, Administrator
Syntax

    end

Usage:

Use this command to return to the Exec mode.
exit

Exits the current mode and returns to the parent configuration mode.
Product:

All
Privilege:

Security Administrator, Administrator
Syntax

    exit

Usage:

Use this command to return to the parent configuration mode.
router-id

Configures the Label Distribution Protocol Router ID.
Platform:

ASR 5000
Product:

GGSN, P-GW, SAEGW
Privilege:

Security Administrator, Administrator
Syntax

    router-id ipv4_addr

    no router-id

no

Disables the router ID.
ipv4_addr

Must be an IPv4 address entered in dotted-decimal notation.
Usage:

This command is used to configure the LDP router-id. This is an optional parameter. If the ID is not configured, the largest operational loopback address is selected as the LDP router ID. If LDP has started, any change will take effect only after disabling and enabling LDP.
Example:

The following command sequence configures an LDP router ID:

    router-id 10.2.3.4

session

Configures the LDP session parameters.
Platform:

ASR 5000
Product:

GGSN, P-GW, SAEGW
Privilege:

Security Administrator, Administrator
Syntax

    session timers { hold-interval integer_value | keepalive-interval integer_value }

    default session timers

default

Configures the default values for hold-interval parameter at 45 and keepalive-interval parameter at 15.
timers

Configures the LDP session keepalive parameters.
hold-interval integer_value

Configures the session hold time interval in seconds.

integer_value is an integer from 45 through 65535.

Default: 45
keepalive-interval integer_value

Configures the frequency of sending keepalive packets in seconds.

integer_value is an integer from 15 through 21845.

Default: 15
Usage:

This optional command is used to configure LDP session timers. LDP session hold-interval is always set to three times the LDP session keepalive-interval. The “default” option sets the session keepalive and hold intervals to the default values.
Example:

The following command sequence configures the LDP session parameters:

    session timers keepalive-interval
    30

    session timers hold-interval
    45

    default session timers