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Forum Replies

  1. Nice explanation, Rene.

    You nicely described in STP, how the affected switch updated CAM table.

    When a link fails (Uplink/Backbone) in RSTP environment, how the affected switch will collect MAC?

  2. Sorry, Shanmugasiva,
    I am not understanding what you are asking. Could you ask this another way?

    If you are asking what this message means, I can try to help.
    setting bridge id (which=3) prio 4097 prio cfg 4096 sysid 1 (on) id 1001.0011.bb0b.3600

    “cfg 4096”
    This means you set (either via spanning-tree vlan 1 4096, or spanning-tree vlan 1 root primary). This is what it means when it says “prio cfg 4096”–the vlan was configured to be priority 4096.

    “prio 4097”
    However, the actual priority is the configured priority + vlan number. So, in this case, the actual p

    ... Continue reading in our forum

  3. Hello Rene,
    I have configured a lab connecting three switches on gns3 (SW1,SW2 and SW3). SW1 is the Root switch. They are connected like this:
    The issue is that as soon as i admin down the port on SW3(e3/2-RP), the other port e3/3 becomes the new RP. This is expected. But when i bring back the port up on SW3(e3/2), the port doesn’t becomes automatically RP again, because its far end device port SW1 (e3/0) is going into err-disabled state, essentially the moment that i admin

    ... Continue reading in our forum

  4. Ok i think i have found the issue here. I have configured udld mode aggressive on all the ports. So that is why when i admin down the port on SW3(e3/2-RP), the Root switch port SW1 (e3/0) goes into err-disable state! Since Root Switch port e3/0 will not receive any traffic, it goes into err-disable state. Finally, i just needed to bounce it, to work as before.

    Also, when i tried to admin down the port on the Root Switch (SW1-e3/0) i noticed that the far end port doesn’t go to the error-disable state, even though the far end port (SW3-e3/2) is configured with ud

    ... Continue reading in our forum

  5. Hello Angelos

    Thanks so much for sharing your experiences with us. It’s great to learn from the learning experiences of others as it helps us all to identify similar situations in our studies and our jobs.

    Once again, greatly appreciated!


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