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Forum Replies

  1. Why does the Root switch has the port Fa0/17 Blocked in the example “Spanning-Tree Disabled”?
    Isn’t that said, that all ports of the root switch should be designated?

    If we disable spanning-tree on SW3 (for VLAN 10), then I guess the SW3 should be transparent for spanning-tree: as if the SW1 would be connected directly with SW2 on all four ports.

  2. Hello Lukasz

    The diagram that you are referring to indicates that port Fa0/17 is a backup port. This is a port role that is available on RSTP (802.1w). It is one of the two types of port roles that exist for the blocking state. So yes, in essence, this port is in a blocking state.

    However, keep in mind that since SW3 does not have spanning-tree activated, as mentioned in the lesson, the STP topology has not converged. A root bridge will have all designated ports once the topology has converged. So essentially, STP root bridge selection has not been complet

    ... Continue reading in our forum

  3. Hi Laz,

    Thanks alot for a very quick detailed response.


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