1-3
z
Whenever mentioned in this document, a router port is a router-connecting port on the switch,
rather than a port on a router.
z
Unless otherwise specified, router/member ports mentioned in this document include static and
dynamic ports.
z
On an MLD Snooping-enabled switch, the ports that received MLD general queries with the source
address other than 0::0 or IPv6 PIM hello messages are dynamic router ports.
Aging timers for dynamic ports in MLD Snooping
Table 1-1
Aging timers for dynamic ports in MLD Snooping and related messages and actions
Timer
Description
Message before
expiry
Action after expiry
Dynamic router
port aging timer
For each dynamic router
port, the switch sets a timer
initialized to the dynamic
router port aging time.
MLD general query of
which the source
address is not 0::0 or
IPv6 PIM hello.
The switch removes
this port from its router
port list.
Dynamic
member port
aging timer
When a port dynamically
joins an IPv6 multicast
group, the switch sets a timer
for the port, which is
initialized to the dynamic
member port aging time.
MLD report message.
The switch removes
this port from the MLD
Snooping forwarding
table.
The port aging mechanism of MLD Snooping works only for dynamic ports; a static port will never age
out.
How MLD Snooping Works
A switch running MLD Snooping performs different actions when it receives different MLD messages, as
follows:
The description about adding or deleting a port in this section is only for a dynamic port. Static ports can
be added or deleted only through the corresponding configurations. For details, see
Configuring Static
Ports
.
