topic Flex10 IGMP snooping and Data-driven IGMP in BladeSystem - General

Flex10 IGMP snooping and Data-driven IGMP

vincentrichard — Tue, 13 Jul 2010 06:54:10 GMT

Hi,

we own a C7000 with two Flex-10 10Gb. Also, we have some B460C G5.

I observe strange behavior of IGMP snooping, it seems that it does not work if the network is not linked to an uplink port. Is it an expected behavior? I observe correct behavior if the network is connected to an uplink port even if multicast traffic is sent and received inside the blade center.

moreover, does the Flex-10 module handle Data-driven IGMP?

Re: Flex10 IGMP snooping and Data-driven IGMP

HEM_2 — Tue, 13 Jul 2010 16:03:34 GMT

There is a specific fix for IGMP Snooping in VC firmware version 2.33, please make sure you are using that version.

Flex-10 does not currently support Data-driven IGMP, in other words it floods all unregistered multicast.

Re: Flex10 IGMP snooping and Data-driven IGMP

Matti_Kurkela — Wed, 14 Jul 2010 12:46:54 GMT

Some Cisco IOS versions also have a similar bug/issue: their IGMP snooping feature does not really work if nobody in the segment is sending IGMP queries.

A multicast-aware router will periodically send IGMP queries, fulfilling the requirement. If the segment is non-routable (e.g. an isolated network segment for security reasons), there is a "IGMP Querier" feature that can fulfill the requirement without an actual multicast router.

See Cisco's document about the problem:
http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a008059a9df.shtml

It lists 5 possible solutions/workarounds. Perhaps some of those ideas are applicable in the blade center too?

MK

Re: Flex10 IGMP snooping and Data-driven IGMP

vincentrichard — Thu, 15 Jul 2010 07:13:21 GMT

HEM, Yes I am already in 2.33 firmware. Thanks for information about Data-driven IGMP.

Matti Kurkela, My problem is not flooding when there is no "IGMP querier" it seems that it is normal for a non Data-driven IGMP Switch. but my problem is that behavior change if it is a network that has an uplink port or has not.

if there is no uplink port even if I have a/some "IGMP querier" the multicast is received on every blades.