we installed recently 2 microsoft servers that use network load balancing configured in NIC cards.
as a consequence, i discovered that any packet sent to these servers is broadcasted to all switch ports!
using sniffer i found that MAc destination address was: MS-NLB-virtserver.
so it seems to be like if cisco switch consider this address as multicast or broadcast, that's why it sends it to all ports.
any suggestion to fix this problem?
i thought about static mac to port mapping, but is it possible to define 2 static entries for the same MAC?
On each of the access switches in the Layer-2 broadcast domain enter the command:
mac address-table static 1111.1111.1111 vlan 10 interface FastEthernet0/1 FastEthernet0/2
Obviously change the MAC address from 1111.1111.1111 and the intefaces to the real interfaces where the Cluster is (you can have several interfaces in the list). If the Cluster isn't directly connected to the switch but the switch is in the same layer-2 domain you will need to add it to the uplink. If you have a redundant (STP) topology you will need to add it to each potential path.