Dell C1048P Port Extender Networking Command-Line Reference Guide for the C900 - Page 1648

rootguard Enter the keyword rootguard to enable root guard on a PVST+ port or port-channel interface. Defaults Not configured. Command Modes INTERFACE Command History This guide is platform-specific. For command information about other platforms, see the relevant Dell Networking OS Command Line Reference Guide. The following is a list of the Dell Networking OS version history for this command. Version 9.9(0.0) 9.2(1.0) 8.3.19.0 8.3.11.1 8.4.2.1 8.3.7.0 8.2.1.0 7.6.1.0 7.5.1.0 7.4.1.0 6.2.1.1 Description Introduced on the C9010. Introduced on the Z9500. Introduced on the S4820T. Introduced on the Z9000. Introduced the loopguard and rootguard options on the ESeries TeraScale, C-Series, and S-Series. Introduced on the S4810. Introduced the hardware shutdown-on-violation option. Introduced on the S-Series. Introduced on the C-Series. Added the optional Bridge Port Data Unit (BPDU) guard. Introduced. Usage Information The BPDU guard option prevents the port from participating in an active STP topology in case a BPDU appears on a port unintentionally, or is misconfigured, or is subject to a DOS attack. This option places the port into the Error Disable state if a BPDU appears, and a message is logged so that the administrator can take corrective action. NOTE: A port configured as an edge port, on a PVST switch, immediately transitions to the forwarding state. Only ports connected to end-hosts should be configured as an edge port. Consider an edge port similar to a port with a spanning-tree portfast enabled. If you do not enable shutdown-on-violation, BPDUs are still sent to the route process module (RPM) CPU. You cannot enable root guard and loop guard at the same time on a port. For example, if you configure loop guard on a port on which root guard is already configured, the following error message is displayed: % Error: RootGuard is configured. Cannot configure LoopGuard. Per-VLAN Spanning Tree Plus (PVST+) 1648