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Spanning Tree

What is the use of following comands on the port where the servers is connected.

spanning-tree bpduguard enable

spanning-tree guard root


Re: Spanning Tree

spanning-tree bpduguard enable:

Causes one interface to become in error-disabled state if it receives a BPDU frame.

spanning-tree guard root:

We know that swA must be the root and we want to ignore any BPDU that will make an other sw as root. So use Root guard.

PR if It Helps

Re: Spanning Tree

spanning-tree bpduguard enable : This command is used on access-ports. Ports with this command still participate in stp process. When this port recv a bpdu from a switch connected on this port, it would go in to err-disable state. Admin will have to manually enable the port.

spanning-tree guard root: if a port recv superior bpdu from a connected switch then the witch sending superior bpdu will become root. This command prohibits the switch sending superior bpdu's from becoming the root & blocks the port recvng such bpdu's. Once bpdu ceases on this port, it again regains the state & functions normally without admin intervention.