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Forum Replies

  1. Hi K,

    The switch with the best bridge ID becomes the root bridge. The bridge ID consists of the priority (default value 32768) and the MAC address.

    With the default settings, it’s up to the MAC address to determine which switch will become root bridge. This applies to all VLANs.


  2. Hi Laz & Hoan,

    The first picture was only used to explain that the logical topology can be different from the physical topology, which is why we use PVST.

    I understand this can be confusing so I added some extra text to explain that in the other examples, we use VLAN 10 + 20 on all three switches.


  3. Hi Heng,

    You can configure a different priority for each VLAN, allowing you to select a different root bridge per VLAN.

  4. Hello Heng.

    If you do not change any of the priorities for root bridge selection, then by default the switch with the lowest bridge ID will be chosen. This means that the same switch will be chosen as the root bridge for all VLANs.

    I hope this has been helpful!


  5. lagapides
    Thank you so much. I got it now.

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