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Forum Replies

  1. Hi Rene,

    I am more curious if STP will send BPDUs on Access ports enabled with Portfast or this will be out of the STP topology, Let be more specific with my query

    In case i have 2 SWs running RSTP a third SW is introduced which happens to be not supporting STP and is connected to my 2 Sws with portfast enabled

    In case BPDUs is being sent on portfast then i assume BPDUGuard will save the day for me on the 2nd SW as it will shut down the port once it receives BPDU on its access port, Is this correct?





  2. Thanks Rene, The point here is usually you don’t know the end host capability, I saw cases loop can happen from a server with NIC bridging without STP capability.

    Just wanted to make sure Portfast + BPDUGuard can address this case



  3. Hi Ahmed,

    In that case it might be wise to enable BPDUguard. If someone connects something that isn’t supposed to send BPDUs then it’s best to shut the interface with BPDUguard :slight_smile:


  4. Hello rosna

    By default, all ports on a switch, including those configured with portfast SENDBPDUs. (It is possible to disable BPDU sending on these ports using BPDU filtering.) Portfast essentially skips the listening and learning states to enter the forwarding state immediately but does not disable STP. It also applies the global BPDUGuard feature (if it is enabled) to all ports configured using portfast.

    In addition, as you mentioned, it won’t send any TC information on that port because by definition, there should be no switches connected to the specific

    ... Continue reading in our forum

  5. Good explanation !!
    I really enjoy reading your topics and make me feel more comfortable and confident.

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