Need help with switch used for ghosting

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May 19th, 2010
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I would like to set up a Cisco 3750 for ghosting on our LAN. The switch would only be used for imaging and configuring. Is there anyway to block the multicast traffic from flooding the rest of the network  ?

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Giuseppe Larosa Wed, 05/19/2010 - 06:40
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Hello Stephen,

if you don't enable PIM in the SVI associated with the Vlan you should be fine.

However, in order to make IGMP snooping to work well you should use the ip igmp snooping querier function

if this feature (igmp snooping querier)  is not supported for correct multicast operation you should disable IGMP snooping for that specific vlan

Hope to help


Mohamed Sobair Wed, 05/19/2010 - 06:53
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1- Block layer-2 multicast with the command (switchport block multicast) at the interface level.

2- Block multicast routing with (ip multicast ttl-threshhold ) command at the interface level between network boundaries.

This should solve your problem,



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