Spanning Tree BPDU Guard is used to disable the port in case a new device tries to enter the already existing topology of STP. Thus devices, which were originally not a part of STP, are not allowed to influence the STP topology. If set to Enable, when a BPDU is received on an edge port, that port is disabled. Once the port has been disabled it requires manual-intervention to be re-enabled. Spanning Tree Root Guard is used to prevent the root of a Spanning Tree instance from changing unexpectedly. The priority of a Bridge ID can be set to zero but another Bridge ID with a lower mac address could also set its priority to zero and take over root. Both are globally set on the switch. If you have any possibility of other networking devices being plugged into the switch without your knowledge. It may be a good idea to enabled these after STP is configured on the network. This way if someone randomly plugs a networking device in with STP on it, it wont throw your network for a loop. Here are some good white pages to have on spanning tree www.dell.com/.../app_note_13.pdf www.dell.com/.../app_note_1.pdf www.dell.com/.../pwcnt_MSTP_interoperability.pdf Thanks
Hi, I have several core Dell switches using PowerConnect 6224s mostly - these ink into my provider's Cisco kit. We run several VLANs and have redundant links between stacked switches. I've read up on spanning tree and have the following tasks: 1. Map out the network - including ID root bridge, root ports, blocked paths, max age and helo time Once I've done my analysis information, I'm not sure how to best optimize the spanning tree config, so far I have: 1. Ensure RSTP is enabled on all switches2. Ensure all edge ports have spanning tree port fast configured3. Do not declare spanning tree port fast on links between switches4. Force speed and duplex settings on all link ports between switches (I assume this is because auto negotiate takes longer?) What I'm not sure about is:1. Should I enable BPDU guard and if so, where?2. Should I enable root guard and if so, where? I've read Todd's informative article: [URL] I'm not sure where\whether I should be configuring the guard options - am happy to provide additional info as needed. Thanks
How should I configure Spanning Tree