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Mulicat forwarding on EX4200 Virtual chassis

03.20.10   |  
‎03-20-2010 11:38 PM

Would anyone know what the following error means:

mcsn[802]: igmpl2_send: vlan 156/v157 not configured!


In have deployed a 4200 dual chassis unit and am having issues with multicast forwarding , specifically with EIGRP. When the affected vlan is deleted and added again this error appears. I can also see the same error appearing for other vlans configured on the unit.  The odd thing is that I have deleted all igmp config from the box? The JunOS is 9.6R1.13.

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Re: Mulicat forwarding on EX4200 Virtual chassis

03.22.10   |  
‎03-22-2010 03:32 PM

Can you rephrase your question? What are you trying to do?


There is a bug in 10.x code in that link local multicast doesn't work if you have igmp-snooping enabled ( I believe it works in 9.6 though.

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Re: Multicast forwarding on EX4200 Virtual chassis

03.23.10   |  
‎03-23-2010 04:10 AM

My question is what does the above alarm mean and why would I get such an alarm on a 4200 virtual chassis where all IGMP config has been deleted?


My problem is that one of our customers uses EIGRP between three sites connected over a common layer2 vlan. One site no longer receives the multicast hello. This happened when we installed a 4200 virtual chassis into the network.


We did install another 4200 in the network at the same time but it doesn't have any problems with forwarding EIGRP multicasts and it too had all its IGMP config deleted. So the problem is not inherent.


Any feedback appreciated

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Re: Multicast forwarding on EX4200 Virtual chassis

03.24.10   |  
‎03-24-2010 07:06 PM

So not sure what the answer is to your alarm question.. However in later version of Junios if you have IGMP-Snooping enabled it prevents the flooding of traffic to the segment. Which by RFC definition should flood all traffic to that group range.


I did not experience this bug in 9.6 code though.. Only 10.x and newer..You could try disabling igmp-snooping and see if that corrects your issue..

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Re: Multicast forwarding on EX4200 Virtual chassis

03.25.10   |  
‎03-25-2010 02:53 AM

Hi Buckweet

Thanks for your input. I have deleted all IGMP and IGMP-snooping config on the 4200, would you be aware if this is different from disabling it?