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New Member


Hi ,

Can some help me on the below scenerios .

SW1 : MAC ( AA)

SW2 : MAC (BB)

SW1 fa0/1  ---------------fa0/1 SW2

1. When a STP BPDU comes out from SW1 its will have Source MAC of the egress interface ( in ethernet header ) and Port ID as fa0/1 inside BPDU

Now What happens in this case

SW 1 ----------- 3 links ------ SW2

3 links are bundled to one PO ( lets say fa0/1-3 )

1. How what will be the Source MAC and port ID in the BPDU that egress from SW1

SW 1 ----------- 3 links ------ SW2

How is the Ether-channel determines which interface should be active in the bundle .

Whether SW1 or SW2 will have this rights .

How is the ether-channel mac picked from the N number of bundled interface.

If i have fa0/1-3 in one group .

Initially the fa0/1 was active and PO MAC was this fa0/1 MAC .

Now i have shut the fa0/1 , so fa0/2 was active and PO MAC changed .

Now brought back fa0/1 . But why wtill fa0/2 is active and PO uses fa0/2 MAC

New Member

In the etherchannel, the

In the etherchannel, the three ports are seen as one STP link.  All links in the ether-channel will be active.  That is the point of etherchanneling. 

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