How do I set root guard?

Configure the Root Guard

  1. Enter Configuration mode for the interface. SEFOS# configure terminal SEFOS(config)# interface extreme-ethernet 0/1.
  2. Configure the port as a trunk port.
  3. Enable the root guard on the port.
  4. Review the root guard output on the port.
  5. Disable the root guard on the interface.

How does Root Guard work?

The STP root guard feature prevents a port from becoming root port or blocked port. If a port configured for root guard receives a superior BPDU, the port immediately goes to the root-inconsistent (blocked) state. Usually STP root guard is configured on primary & secondary root switches.

What is Root Guard and BPDU Guard in STP?

Root-guard will stop a superior bpdu from becoming the root. Bpdu guard will stop another switch from connecting entirely by shutting the port down.

What is configuration Bpdu?

Bridge Protocol Data Units (BPDUs) are frames that contain information about the spanning tree protocol (STP). Configuration BPDU, sent by root bridges to provide information to all switches.

What is spanning tree guard loop?

Spanning tree is used to ensure a loop-free topology over the LAN. Occasionally a hardware or software failure can cause STP to fail, creating STP/ forwarding loops that can cause network failures where unidirectional links are used.

What is root guard in Cisco switch?

In other words, Root Guard feature of Cisco Switches prevents a Designated Port from becoming a Root Port. Root Guard feature can be enabled on switch ports that is connected to other switches that should never become a Root Bridge.

What are the two reasons to use root Guard?

Root guard is an STP feature that is enabled on a port-by-port basis; it prevents a configured port from becoming a root port. Root guard prevents a downstream switch (often misconfigured or rogue) from becoming a root bridge in a topology.

What scenario might be ideal for the use of root guard in configuring a switch?

What scenario might be ideal for the use of root guard in configuring a switch? You wish to prevent switches beyond a certain port from becoming the root bridge, but still wish to use STP.

What is BPDU filter and BPDU guard?

BPDU filter will prevent inbound and outbound BPDU but will remove portfast state on a port if a BPDU is received. On the other hand, BPDU Guard keeps an eye open for any BPDU’s entering the interfaces that are enabled this feature. The port will disable as soon as the first BPDU is received, by shutting the port down.

What is a BPDU guard?

BPDU Guard feature is used to protect the Layer 2 Spanning Tree Protocol (STP) Topology from BPDU related attacks. When a BPDU Guard enabled port receive BPDU from the connected device, BPDU Guard disables the port and the port state is changed to Errdisable state.