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Forum Replies

  1. Hi Rene,
    In blocking port state,switch not able to receive and transmit any BPDUs,then How blocking port state move to listening state.


  2. Mohammad,
    The concept of an Alternate port was introduced with Rapid Spanning Tree. This feature takes over what the traditional (802.1 D) spanning-tree enhancement of “uplink-fast” used to do. The Alternate port serves as a “hot-standby” for a switch’s Root Port, but Alternate Port is considered to be in a Discarding state (Discarding is the RSTP term for Blocking, Listening, and Disabled for spanning-tree).

    This means that an Alternate port can receive BPDUs but will not send them. As soon as a Root Port fails, the Alternate Port will immediately transitio

    ... Continue reading in our forum

  3. Hello Rene

    In your post you mentioned ports in block mode take the 20+15+15 before forwarding in some cases. Could you tell me in which case cause i was trying to simulate but i only got lis->lear->for states and not Max age time.

    Thanks in advance.

  4. Hello Jose

    There are two situations which require a switch to begin STP convergence procedures. The direct and indirect link failures. Let’s take a look at both:

    1. A direct link failure is when a switch detects a loss of carrier on its own port and immediately declares the port as disconnected. Take a look at the following figure:


    The STP is converged and Port B is in blocking state. Imagine Port A goes down. The bridge no longer detects a carrier on tha

    ... Continue reading in our forum

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