[126488] in North American Network Operators' Group
RE: IPv4 Multicast
daemon@ATHENA.MIT.EDU (Tony Bunce)
Tue May 18 20:44:58 2010
From: Tony Bunce <tonyb@go-concepts.com>
To: Rens <rens@autempspourmoi.be>
Date: Wed, 19 May 2010 00:44:34 +0000
In-Reply-To: <F7B48C68C2B34D8081F95254346434A1@EU.corp.clearwire.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
>>I can see that IGMP is enabled on all interfaces but do I need enable som=
ething else?
You need to have a multicast router or enable IGMP querier on one of your s=
witches. For IGMP snooping to work something on the network has to be send=
ing out PIM hellos or IGMP query messages. Without that the switch will fl=
ood multicast traffic to all ports
"The reason for this issue is that IGMP snooping is not really supported on=
any Catalyst platform without an mrouter."
http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note091=
86a008059a9df.shtml#understand
Note if you go the router method ALL multicast traffic will be sent to the =
router, so don't expect it to work if you have 5Gbps of multicast connected=
to a router with a 1Gbps interface.
If all your multicast traffic is on the same layer2 network then the IGMP q=
uerier feature should work fine.
-Tony
