IGMP snooping + vlan + 4500

Unanswered Question
Jul 16th, 2008
User Badges:


i have configured igmp snooping in the 4500 in the created vlan. in the remote switch i add a specific port to this vlan but i dont receive any multicast traffic?!

please could someone help me? any specific document!


  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Kevin Dorrell Wed, 07/16/2008 - 13:41
User Badges:
  • Green, 3000 points or more

You need to understand that IGMP snooping is used to restrict the flooding of multicasts rather than to allow it.

Without IGMP snooping, multicasts would get flooded to all ports on the VLAN.

If you are running IGMP snooping, then the switch does not flood the multicasts. Instead, it listens to the IGMPs from the hosts, and only sends the multicasts to those switchports where a host is generating IGMP reports for the multicast group.

So, if you have IGMP snooping, and you do not see the multicast stream on the port, then maybe the host on that port is not generating IGMPs.

Kevin Dorrell


habouzyad Tue, 07/22/2008 - 10:19
User Badges:


like described in the topology (see in the attachements), i want to configure multicast (igmp snooping) in vlan 3 , the way to have possiblity to connect to the video server from any Pc connected to the Vlan 3.

the swith connected to the video server is from another constructor.

see in the attachement:

1- topology

2- Configuration in the 4500

3- show igmp

Many thanks in advance for your help




This Discussion