What is spanning tree vlan priority?

To ensure that a switch has the lowest bridge priority value, use the spanning-tree vlan vlan-id root primary command in global configuration mode. The priority for the switch is set to the predefined value of 24,576 or to the highest multiple of 4096 less than the lowest bridge priority detected on the network.

What is spanning tree priority?

Every switch taking part in spanning tree has a bridge priority. The switch with the lowest priority becomes the root bridge. If there’s a tie, then the switch with the lowest bridge ID number wins. The problem is that, by default, every switch has the same priority value (32768).

What is spanning tree priority 0?

Setting value to 0 (spanning-tree priority 0) sets the root bridge permanently so that it won’t ever change without you wanting it. If you have 2 core switches, set the other one to priority 1 so that if the main core fails the whole network will switch to the other one.

How do I change spanning tree port priority?

We can change the Spanning Tree Port Priority value, using the interface configuration commad “spanning-tree vlan port-priority “, as shown below. You may change the Spanning Tree Port Priority value only in increments of 16.

How to change the VLAN priority in spanning-tree?

This command is used to change the VLAN priority for spanning-tree. In the below example we will configure SW2’s priority of Vlan 1 to be 4096. Notice the priority is now 4096 and the switch is now is root.

How to set root bridge priority in spanning tree?

If an alternate root bridge is desired, use the spanning-tree vlan vlan-id root secondary global configuration mode command. This command sets the priority for the switch to the predefined value 28,672.

Which is the root of the VLAN priority 0?

The priority order starts from 0 and then increases in 4096. 0, 4096, 8192, 12288, … If you configure two switches one of them with priority ¨0¨ and the other one with priority ¨4096¨, the first one with priority ¨0¨ is going to be the root.

Which is the default STP value for root bridge?

Re: STP Priority Values. Default STP priority is 32768. The lower the priority the more likely the switch is to be come the root bridge. However you normally have to do STP in incerments of 4096 so you would not be able to allocate a priority of 1 to a switch.