Edge-Core ECS4610-24F, Management Manual

Page: 917 / 1154

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HAPTER
39
| Multicast Filtering Commands
IGMP Snooping
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OMMAND
M
ODE
Global Configuration
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OMMAND
U
SAGE
IGMP Snooping uses a null IP address of 0.0.0.0 for the source of IGMP
query messages which are proxied to downstream hosts to indicate that it
is not the elected querier, but is only proxying these messages as defined
in RFC 4541. The switch also uses a null address in IGMP reports sent to
upstream ports.
Many hosts do not implement RFC 4541, and therefore do not understand
query messages with the source address of 0.0.0.0. These hosts will
therefore not reply to the queries, causing the multicast router to stop
sending traffic to them.
To resolve this problem, the source address in proxied IGMP query and
report messages can be replaced with any valid unicast address (other
than the router's own address) using this command.
E
XAMPLE
The following example sets the source address for proxied IGMP query
messages to 10.0.1.8.
Console(config)#ip igmp snooping vlan 1 proxy-address 10.0.1.8
Console(config)#
ip igmp snooping
vlan query-interval
This command configures the interval between sending IGMP general
queries. Use the no form to restore the default.
S
YNTAX
ip igmp snooping vlan vlan-id query-interval interval
no ip igmp snooping vlan vlan-id query-interval
vlan-id - VLAN ID (Range: 1-4093)
interval - The interval between sending IGMP general queries.
(Range: 10-31744 seconds)
D
EFAULT
S
ETTING
100 (10 seconds)
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OMMAND
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Global Configuration
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OMMAND
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SAGE
◆
An IGMP general query message is sent by the switch at the interval
specified by this command. When this message is received by
downstream hosts, all receivers build an IGMP report for the multicast
groups they have joined.