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  1. awesome explaination Renee .
    I really enjoy reading your topics and make me feel more confortable and confident when I learn it

  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 port.

    The reason we use BPDUGuard is because we don’t want any switches to be connected to a port configured with portfast. It is only for end devices. So if a BPDU is RECEIVED, the port goes into err-disabled state, essentially shutting down.

    I hope this has been helpful!


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

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