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Static MAC address entry on IOS (3500XL) vs CatOS (6500 sup2)


In order to control the behaviour of Microsoft Network Load Balancing (MSNLB), I am trying to enter some static MAC addresses into our switched network. The command is very straightforward in CatOS (6.3) on the 6500 :

set cam permanent <hw-add> <mod/port>

This I understand.

The command in IOS takes additional paramemeters, the one that I don't understand is an 'in-port'.

mac-address-table static <hw-addr> <in-port> <out-port-list>

What is the purpose of this parameter ? How would I specify all interfaces (fa0/1-24, gi0/1-2, on a 3524XL) for an in-port ? I have searched the Cisco site with little success.

Also, while I'm here asking about this, it also seems possible to enter multiple 'out-port's in the 3500XL IOS. So, with our NLB situation, can I enter the bogus-MAC-for-MSNLB as the hw-add, and the two interfaces to the NLB machines as the out-port-list, and then have the switch flood only these two interfaces ? Currenty the NLB 'feature' is flooding a few more ports than needed, to say the least.

Thanks for any comments,


Community Member

Re: Static MAC address entry on IOS (3500XL) vs CatOS (6500 sup2

You have to add a separete entry for each in-port.

mac-address-table static fast 0/1 fast 0/24

mac-address-table static fast 0/2 fast 0/24

Yes, traffic will only flood to the two specified (output) interfaces.

In the 6500 (either catos or native) you can specify only one outgoing interface for unicast mac, meaning that you can't connect the NLB vip interfaces to the 6500 switch ports (u can if using a hub between the switch port and the cluster or flood the traffic or using multicast). What is the prefered method? Is it better to use server load balancing?

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