Extreme Networks ExtremeWare XOS 11.3, Руководство пользователя

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IP Multicast Routing
ExtremeWare XOS 11.3 Concepts Guide
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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 leave message, but the port that requests removal
is removed from the IGMP snooping table.
If the last port within a VLAN sends an IGMP leave message and the router does not receive any
responses to the query, then the router immediately removes the VLAN from the multicast group.
Static IGMP
To receive multicast traffic, a host must explicitly join a multicast group by sending an IGMP 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 IGMP 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 IGMP groups when an
IGMP 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. Static IGMP is only available with
IGMPv2.
Use the following command to emulate a host on a port:
configure igmp snooping {vlan} <vlanname> ports <portlist> add static group <ip
address>
To emulate a multicast router on a port, use the following command:
configure igmp snooping {vlan} <vlanname> ports <portlist> add static router
To remove these entries, use the corresponding command:
configure igmp snooping {vlan} <vlanname> ports <portlist> delete static
group [<ip_address> | all]
configure igmp snooping vlan <vlanname> ports <portlist> delete static router
To display the IGMP snooping static groups, use the following command:
show igmp snooping vlan <name> static [group | router]
IGMP Snooping Filters
IGMP snooping filters allow you to configure a policy file on a port to allow or deny IGMP report and
leave packets coming into the port. (For details on creating policy files, see
“Policy Manager” on
page 257 .) IGMP snooping filters is available with IGMPv2 and IGMPv3.
For the policies used as IGMP snooping filters, all the entries should be IP address type entries, and the
IP address of each entry must be in the class-D multicast address space but should not be in the
multicast control subnet range (224.0.0.x/24). After you create a policy file, use the following command
to associate the policy file and filter a set of ports:
configure igmp snooping vlan <vlanname> ports <portlist> filter [<policy> | none]
To remove the filter, use the
none
option.