Chapter 20
| Multicast Filtering Commands
IGMP Snooping
– 472 –
◆
Advertisements are sent by routers to advertise that IP multicast forwarding is
enabled. These messages are sent unsolicited periodically on all router
interfaces on which multicast forwarding is enabled. They are sent upon the
expiration of a periodic timer, as a part of a router's start up procedure, during
the restart of a multicast forwarding interface, and on receipt of a solicitation
message. When the multicast services provided to a VLAN is relatively stable,
the use of solicitation messages is not required and may be disabled using the
no ip igmp snooping vlan mrd
command.
◆
This command may also be used to disable multicast router solicitation
messages when the upstream router does not support MRD, to reduce the
loading on a busy upstream router, or when IGMP snooping is disabled in a
VLAN.
Example
This example disables sending of multicast router solicitation messages on VLAN 1.
Console(config)#no ip igmp snooping vlan 1 mrd
Console(config)#
ip igmp snooping vlan
proxy-address
This command configures a static source address for locally generated query and
report messages used by IGMP proxy reporting. Use the
no
form to restore the
default source address.
Syntax
[
no
]
ip igmp snooping vlan
vlan-id
proxy-address
source-address
vlan-id
- VLAN ID (Range: 1-4093)
source-address
- The source address used for proxied IGMP query and
report, and leave messages. (Any valid IP unicast address)
Default Setting
0.0.0.0
Command Mode
Global Configuration
Command Usage
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.
Summary of Contents for EX-3524
Page 2: ......
Page 28: ...Figures 28 ...
Page 34: ...Section I Getting Started 34 ...
Page 58: ...Chapter 1 Initial Switch Configuration Setting the System Clock 58 ...
Page 72: ...Chapter 2 Using the Command Line Interface CLI Command Groups 72 ...
Page 156: ...Chapter 5 SNMP Commands Notification Log Commands 156 ...
Page 164: ...Chapter 6 Remote Monitoring Commands 164 ...
Page 218: ...Chapter 7 Authentication Commands Management IP Filter 218 ...
Page 268: ...Chapter 8 General Security Measures Port based Traffic Segmentation 268 ...
Page 292: ...Chapter 9 Access Control Lists ACL Information 292 ...
Page 312: ...Chapter 10 Interface Commands Power Savings 312 ...
Page 324: ...Chapter 11 Link Aggregation Commands Trunk Status Display Commands 324 ...
Page 366: ...Chapter 15 Address Table Commands 366 ...
Page 428: ...Chapter 17 VLAN Commands Configuring Voice VLANs 428 ...
Page 572: ...Chapter 25 IP Interface Commands IPv6 Interface 572 ...
Page 578: ...Section I Appendices 578 ...