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Can static MAC address cause loops

Hi Folks,

If I configure a static mac entry, like:

mac address-table static 1111.2222.3333 vlan 10 int g2/0/1

What will happen if traffic with DMAC of 1111.2222.3333 arrives on g2/0/1?

Also, what will a switch do if I apply the following config:

mac address-table static 1111.2222.3333 vlan 10 int g2/0/1

mac address-table static 1111.2222.3333 vlan 10 int g2/0/2

Will the switch forward traffic to both ports? or prefer one more than the other?

Thanks

Alan

1 REPLY
Hall of Fame Super Silver

Re: Can static MAC address cause loops

Hello Alan,

1) the frame will be ignored because from the point of view of the switch the frame doesn't need to be propagated (EARL function) this happened every day when access layer was made with hubs: local traffic is kept local by the mac address filtering function

2) the second command should overwrite the first

Hope to help

Giuseppe

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