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RSTP topology change

  • 1.  RSTP topology change

     
    Posted 01-24-2021 12:20
    Hi.

    I had two questions about RSTP topology changes. 

    1: When an RSTP switch S1 has a port that moves from blocking to forwarding, does it it send a TCN BPDU (BPDU with TC bit set) out just the newly forwarding port? Or does it send it out of all  non-edge forwarding ports?

    2: When another switch receives this TCN BPDU, it flushes the MAC addresses learnt on all its ports except edge ports and the port receiving the TCN message. However, does originating switch S1 flush any MAC addresses?

    Many thanks,
    Deepak


  • 2.  RE: RSTP topology change

     
    Posted 01-25-2021 10:31
    RSTP BDPUs with the TC flag set are sent out of all designated ports and the root port.
    Originating switch flushes MAC addresses on all its ports except edge ports .

    Regards, 


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