Extreme Networks ExtremeWare XOS 11.3, Manual

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IPv6 Multicast Routing
ExtremeWare XOS 11.3 Concepts Guide
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MLD snooping is enabled by default on the switch. If MLD snooping is disabled, all MLD and IP
multicast traffic floods within a given VLAN. MLD snooping expects at least one device on every
VLAN to periodically generate MLD query messages.
When a port sends an MLD done message, the switch removes the MLD snooping entry after 1000
milliseconds (the leave time is configurable, ranging from 0 to 10000 ms). The switch sends a query to
determine which ports want to remain in the multicast group. If other members of the VLAN want to
remain in the multicast group, the router ignores the done message, but the port that requests removal
is removed from the MLD snooping table.
If the last port within a VLAN sends an MLD done message and the router does not receive any
responses to the query, then the router immediately removes the VLAN from the multicast group.
Static MLD
To receive multicast traffic, a host must explicitly join a multicast group by sending an MLD report;
then, the traffic is forwarded to that host. In some situations, you would like multicast traffic to be
forwarded to a port where a multicast-enabled host is not available (for example, when you test
multicast configurations).
Static MLD emulates a host or router attached to a switch port, so that multicast traffic is forwarded to
that port, and the switch will send a proxy join for all the statically configured MLD groups when an
MLD query is received. You can emulate a host to forward a particular multicast group to a port; and
you may emulate a router to forward all multicast groups to a port.
Use the following command to emulate a host on a port:
configure mld snooping {vlan} <vlanname> ports <portlist> add static
group <v6grpipaddress>
To emulate a multicast router on a port, use the following command:
configure mld snooping {vlan} <vlanname> ports <portlist> add static router
To remove these entries, use the corresponding command:
configure mld snooping {vlan} <vlanname> ports <portlist> delete static group [all |
<v6grpipaddress>]
configure mld snooping {vlan} <vlanname> ports <portlist> delete static router
To display the MLD snooping static groups, use the following command:
show mld snooping vlan <name> static [group | router]