Web Management Guide

Table Of Contents
Chapter 19
| Multicast Routing
Configuring PIMv6 for IPv6
– 624
Configuring PIMv6
Interface Settings
Use the Routing Protocol > PIM6 > Interface page configure the routing protocol’s
functional attributes for each interface.
Command Usage
Most of the attributes on this page are common to both PIM6-DM and PIM6-
SM. Select Dense or Sparse Mode to display the common attributes, as well as
those applicable to the selected mode.
An IPv6 address must first be assigned to the required routing interface before
PIMv6 can be configured on this page.
PIMv6 and MLD proxy cannot be used at the same time. When an interface is
set to use PIMv6 Dense mode, MLD proxy cannot be enabled on any interface
of the switch (see “MLD Proxy Routing” in the CLI Reference Guide). Also, when
MLD proxy is enabled on an interface, PIMv6 cannot be enabled on any
interface.
PIM6-DM
PIM6-DM functions similar to DVMRP by periodically flooding the network with
traffic from any active multicast server. It also uses MLD to determine the
presence of multicast group members. The main difference, is that it uses the
routers unicast routing table to determine if the interface through which a
packet is received provides the shortest path back to the source.
Dense-mode interfaces are subject to multicast flooding by default, and are
only removed from the multicast routing table when the router determines
that there are no group members or downstream routers, or when a prune
message is received from a downstream router.
PIM6-SM
A PIM6-SM interface is used to forward multicast traffic only if a join message is
received from a downstream router or if group members are directly connected
to the interface. When routers want to receive a multicast flow, they
periodically send join messages to the RP, and are subsequently added to the
shared path for the specified flow back up to the RP. If routers want to join the
source path up through the SPT, they periodically send join messages toward
the source. They also send prune messages toward the RP to prune the shared
path once they have connected to the source through the SPT, or if there are no
longer any group members connected to the interface.