What is the difference between BPDU guard and BPDU filter?
What is the difference between BPDU guard and BPDU filter?
Enabling BPDU filtering on an interface is the same as disabling spanning tree on it and can cause spanning-tree loops. On the other hand, BPDU Guard keeps an eye open for any BPDU’s entering the interfaces that are enabled this feature.
What is BPDU filter in STP?
The STP BPDU filter feature allows control of spanning tree participation on a per-port basis. It can be used to exclude specific ports from becoming part of spanning tree operations. A port with the BPDU filter enabled will ignore incoming BPDU packets and stay locked in the spanning tree forwarding state.
How many types of BPDUs does STP use?
two types
STP uses two types of BPDUs, configuration BPDUs and topology change notification (TCN) BPDUs.
What are the two BPDU types used by 802.1 D?
There are two kinds of BPDUs for 802.1D Spanning Tree:
- Configuration BPDU, sent by root bridges to provide information to all switches.
- TCN (Topology Change Notification), sent by bridges towards the root bridge to notify changes in the topology, such as port up or port down.
Where are BPDU filters used?
BPDU filter is a feature used to filter sending or receiving BPDUs on a switchport. It is extremely useful on those ports which are configured as portfast ports as there is no need to send or receive any BPDU messages on of these ports. BPDU filter can be configured globally or under the interface level.
What is the purpose of STP BPDUs?
The basic purpose of the Bridge Protocol Data Units (BPDUs) and the Spanning Tree Algorithm (STA) is to avoid Layer 2 Switching loops and Broadcast storms.
What does an interface configured with BPDU guard do when it receives a BPDU packet?
When the STP port receives a BPDU, it is put in the error-disabled state. The BPDU guard feature provides a secure response to invalid configurations because you must manually put the interface back in service.
Does router send BPDU?
No, the router will not trigger the BPDUguard feature in your switch since Routers do NOT send BPDUs.
What is spanning tree BPDU guard?
The BPDU guard feature provides a secure response to invalid configurations because you must manually put the interface back in service. Use the BPDU guard feature in a service-provider network to prevent an access port from participating in the spanning tree.