Web Management Guide-R06

Chapter 20 | Multicast Routing
Configuring PIMv6 for IPv6
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forwarding a control message down the distribution tree, refreshing the prune
state on the outgoing interfaces of each router in the tree. This also enables PIM
routers to recognize topology changes (sources joining or leaving a multicast
group) before the default three-minute state timeout expires.
This command is only effectively for interfaces of first hop, PIM-DM routers that
are directly connected to the sources of multicast groups.
Sparse-Mode Attributes
◆ DR Priority – Sets the priority advertised by a router when bidding to become
the Designated Router (DR). (Range: 0-4294967294; Default: 1)
More than one PIM-SM router may be connected to an Ethernet or other
shared-media LAN. If multicast hosts are directly connected to the LAN, then
only one of these routers is elected as the DR, and acts on behalf of these hosts,
sending periodic Join/Prune messages toward a group-specific RP for each
group. A single DR is elected per interface (LAN or otherwise) using a simple
election process.
The router with the highest priority configured on an interface is elected as the
DR. If more than one router attached to this interface uses the same priority,
then the router with the highest IP address is elected to serve as the DR.
If a router does not advertise a priority in its hello messages, it is assumed to
have the highest priority and is elected as the DR. If more than one router is not
advertising its priority, then the router with the highest IP address is elected to
serve as the DR.
◆ Join/Prune Interval – Sets the interval at which join/prune messages are sent.
(Range: 1-65535 seconds; Default: 60 seconds)
By default, the switch sends join/prune messages every 60 seconds to inform
other PIM-SM routers about clients who want to join or leave a multicast group.
Use the same join/prune message interval on all PIM-SM routers in the same
PIM-SM domain, otherwise the routing protocol’s performance will be
adversely affected.
The multicast interface that first receives a multicast stream from a particular
source forwards this traffic only to those interfaces on the router that have
requests to join this group. When there are no longer any requesting groups on
that interface, the leaf node sends a prune message upstream and enters a
prune state for this multicast stream. The protocol maintains both the current
join state and the pending RPT prune state for this (source, group) pair until the
join/prune interval timer expires.
Web Interface
To configure PIMv6 interface settings:
1. Click Routing Protocol, PIM6, Interface.
2. Modify any of the protocol parameters as required.