R0106-HP MSR Router Series IP Multicast Configuration Guide(V7)

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Figure 69 MLD snooping related ports
The following describes the ports involved in MLD snooping, as shown in Figure 69:
• Router port—Layer 3 multicast device-side port. Layer 3 multicast devices include DRs and MLD
queriers. In Figure 69, Gi
gabitEthernet 1/0/1 of Switch A and GigabitEthernet 1/0/1 of Switch B
are the router ports. A switch records all its local router ports in a router port list.
Do not confuse the "router port" in MLD snooping with the "routed interface" commonly known as
the "Layer 3 interface." The router port in MLD snooping is a Layer 2 interface.
• Member port—Multicast receiver-side port. In Figure 69, Gi
gabitEthernet 1/0/2 and
GigabitEthernet 1/0/3 of Switch A and GigabitEthernet 1/0/2 of Switch B are member ports. A
switch records all its local member ports in its MLD snooping forwarding table.
Unless otherwise specified, router ports and member ports in this document include both static and
dynamic router ports and member ports.
NOTE:
W
hen MLD snooping is enabled, all ports that receive IPv6 PIM hello messages or MLD
g
eneral queries
w
ith a source IP address other than 0::0 are considered dynamic router ports. For more information abou
t
IPv6 PIM hello messages, see "Configuring IPv6 PIM."
Aging timers for dynamic ports in MLD snooping
Timer Description
Message received
before the timer
ex
p
ires
Action after the timer
expires
Dynamic
router port
aging timer
When a port receives an expected
message, the Layer 2 device starts or
resets an aging timer. When the timer
expires, the dynamic router port ages
out.
MLD general queries with
the source address other
than 0::0 or IPv6 PIM
hello messages.
The Layer 2 device
removes the port from
its router port list.
Dynamic
member port
aging timer
When a port dynamically joins a
multicast group, the Layer 2 device
starts or resets an aging timer for the
port. When the timer expires, the
dynamic member port ages out.
MLD report messages.
The Layer 2 device
removes the port from
the MLD snooping
forwarding table.