Dell PowerConnect M6220 Command Line Interface Guide - Page 474
spanning-tree bpdu-protection, Syntax, Default Configuration, Command Mode, User Guidelines, Example
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www.dell.com | support.dell.com spanning-tree bpdu-protection Use the spanning-tree bpdu-protection command in Global Configuration mode to enable BPDU protection on a switch. Use the no form of this command to resume the default status of BPDU protection function. For an access layer device, the access port is generally connected to the user terminal (such as a desktop computer) or file server directly and configured as an edge port to implement the fast transition. When the port receives a BPDU packet, the system sets it to non-edge port and recalculates the spanning tree, which causes network topology flapping. In normal cases, these ports do not receive any BPDU packets. However, someone may forge BPDU to maliciously attack the switch and cause network flapping. RSTP provides BPDU protection function against such attack. After BPDU protection function is enabled on a switch, the system disables an edge port that has received BPDU and notifies the network manager about it. The disabled port can only be enabled by the no version of the command. Syntax spanning-tree bpdu-protection no spanning-tree bpdu-protection Default Configuration BPDU protection is not enabled. Command Mode Global Configuration mode User Guidelines This command has no user guidelines. Example The following example enables BPDU protection. console(config)#spanning-tree bpdu-protection spanning-tree cost Use the spanning-tree cost command in Interface Configuration mode to configure the spanning-tree path cost for a port. To return to the default port path cost, use the no form of this command. 474
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