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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-12247-04
Chapter 44 Configuring IP Multicast Routing
Configuring Optional IGMP Features
To cancel membership in a group, use the
no
ip igmp join-group
group-address
interface configuration
command.
This example shows how to enable the switch to join multicast group 255.2.2.2:
Switch(config)#
interface gigabitethernet1/0/1
Switch(config-if)#
ip igmp join-group 255.2.2.2
Controlling Access to IP Multicast Groups
The switch sends IGMP host-query messages to find which multicast groups have members on attached
local networks. The switch then forwards to these group members all packets addressed to the multicast
group. You can place a filter on each interface to restrict the multicast groups that hosts on the subnet
serviced by the interface can join.
Beginning in privileged EXEC mode, follow these steps to filter multicast groups allowed on an
interface. This procedure is optional.
Step 4
end
Return to privileged EXEC mode.
Step 5
show ip igmp interface
[
interface-id
]
Verify your entries.
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface
interface-id
Specify the interface to be configured, and enter interface
configuration mode.
Step 3
ip igmp access-group
access-list-number
Specify the multicast groups that hosts on the subnet serviced by an
interface can join.
By default, all groups are allowed on an interface.
For
access-list-number
, specify an IP standard access list number.
The range is 1 to 99.
Step 4
exit
Return to global configuration mode.
Step 5
access-list
access-list-number
{
deny
|
permit
}
source
[
source-wildcard
]
Create a standard access list.
•
For
access-list-number
, specify the access list created in Step 3.
•
The
deny
keyword denies access if the conditions are matched.
The
permit
keyword permits access if the conditions are
matched.
•
For
source
, specify the multicast group that hosts on the subnet
can join.
•
(Optional) For
source-wildcard
, enter the wildcard bits in dotted
decimal notation to be applied to the source. Place ones in the bit
positions that you want to ignore.
Recall that the access list is always terminated by an implicit deny
statement for everything.
Step 6
end
Return to privileged EXEC mode.
