NLB with 6509

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Jan 19th, 2009
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Hello All,

Need help to configure 6509 for Microsoft NLB.

NLB is Multicast enabled with Virtual mac-address of 0300.5exx.xxxx

Cisco 6509 running 12.2(18)SXF9

When configuring the 6509 as per the document


mac-address-table static 0300.5e11.1111 vlan 200

interface fa2/3 fa2/4 disable-snooping


will not have disable-snooping option available to configure.

However when the IGMP Multicast support option on the NLB, the mac-address will changes to 0100.5exx.xxxx and I am able to disable-snooping

According to the document

IGMP snooping constrains traffic in MAC multicast groups 0100.5e00.0001 to 0100.5eff.ffff.

does it mean if you the mac-address is 0300.5exx.xxxx you need not or cannot disable snooping due to IGMP Constraints, if so does this configuring 6000 for NLB is incorrect

Thank you in advance.



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HEMANTH_KUMAR Fri, 01/23/2009 - 07:46
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NLB generated 0100.5exx.xxxx when IGMP support is enabled and 0300.5exx.xxxx when disabled.

disable-snooping option is only available when using the mac-address of 0100.5exx.xxxx and not when address beigns 0300.5e.

Permanent Multicast address range is - and and hence they will not come under IGMP snooping, however the range is outside this so we should be able to disable-snoop but option is not available or not required.




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