Alcatel-Lucent 7750 SR OS Service Manual page 1053

no three-way-hello
Context config>service>vprn>pim>interface
config>service>vprn>pim>mdt>default
Description
This command configures the compatibility mode for enabling the three way hello.
Parameters
compatibility-mode — Specifies to enable the three way hello.
tracking-support
Syntax [no] tracking-support
Context config>service>vprn>pim>interface
config>service>vprn>pim>mdt>default
Description
This command sets the the T bit in the LAN Prune Delay option of the Hello Message. This indicates
the router's capability to disable Join message suppression.
Default
no tracking-support
mdt
Syntax mdt
Context config>service>vprn>pim>interface
Description
This command enables the context for a multicast distribution tree (MDT) to carry multicast traffic
from customer sites associated with the multicast domain. Multicast-capable routers create
distribution trees that control the path that IP multicast traffic takes through the network to deliver
traffic to all receivers. There are two types of MDTs, source trees and shared trees. The root of the
source tree is the source of the multicast tree whose branches form a spanning tree through the
network to the receivers. It is also referred to as a shortest path tree (SPT) because the tree uses the
shortest path through the network.
Shared trees use a common root that is placed at a specific place in the network. This shared root is
called the rendezvous point (RP).
All PEs that are configured with the same MDT address will become members of this group and
receive multicast traffic from each other.
The source address used in MDT group address packets is the loopback address configured for the
VPRN, if the loopback address is removed the service we will attempt to find another loop-back
address for the VPRN instance, if no loopback address exists then multicast tunnel for the VPRN
instance will be administratively down. The show command will reflect the reason why the PIM-SM
instance is down.
Addressing conflicts in the core can be avoided by installing import policies on the main PIM access
interfaces.
To enable multicast in a VPRN this parameter must be configured. If it is not configured, no PIM-SM
will not be initialized for this VPRN, and the show command will indicate that the default MDT
address is missing. If the address is removed using the no form of this command, Multicast will be
shut down for this instance and an error indication is displayed when a show command is executed.
7750 SR OS Services Guide
Virtual Private Routed Network Services
Page 1053