Dell MX5108n OS10 Enterprise Edition User Guide for PowerEdge MX IO Modules Re - Page 216

Configure EdgePort OS10(conf-if-eth1/1/4)# spanning-tree port type edge View interface status OS10# show spanning-tree interface ethernet 1/1/4 ethernet1/1/4 of MSTI 0 is designated Forwarding Edge port:yes port guard :none (default) Link type is point-to-point (auto) Boundary: YES bpdu filter :disable bpdu guard :disable bpduguard shutdown-on- violation :disable RootGuard: disable LoopGuard disable Bpdus (MRecords) sent 610, received 5 Interface Designated Name PortID Prio Cost Sts Cost Bridge ID PortID ethernet1/1/4 128.272 128 500 FWD 0 32768 90b1.1cf4.a911 128.272 Spanning-tree extensions STP extensions provide a means to ensure efficient network convergence by securely enforcing the active network topology. OS10 supports BPDU filtering, BPDU guard, root guard, and loop guard STP extensions. BPDU filtering BPDU guard Root guard Loop guard Protects the network from unexpected flooding of BPDUs from an erroneous device. Enabling BPDU Filtering instructs the hardware to drop BPDUs and prevents flooding from reaching the CPU. BPDU filtering is enabled by default on Edge ports. All BPDUs received on the Edge port are dropped. If you explicitly configure BPDU filtering on a port, that port drops all BPDUs that it receives. Blocks the L2 bridged ports and LAG ports connected to end hosts and servers from receiving any BPDUs. When you enable BPDU guard, it places a port (bridge or LAG) in the Error_Disable or Blocking state if the port receives any BPDU frames. In a LAG, all member ports (including new members) are placed in the Blocking state. The network traffic drops but the port continues to forward BPDUs to the CPU that are later dropped. To prevent further reception of BPDUs, configure a port to shut down using the shutdown command. The port can only resume operation from Shutdown state after manual intervention. Avoids bridging loops and preserves the root bridge position during network transitions. STP selects the root bridge with the lowest priority value. During network transitions, another bridge with a lower priority may attempt to become the root bridge and cause unpredictable network behavior. Configure the spanning-tree guard root command to avoid such an attempt and preserve the position of the root bridge. Root guard is enabled on ports that are designated ports. The root guard configuration applies to all VLANs configured on the port. Prevents L2 forwarding loops caused by a hardware failure (cable failure or an interface fault). When a hardware failure occurs, a participating spanning tree link becomes unidirectional and a port stops receiving BPDUs. When a blocked port stops receiving BPDUs, it transitions to a Forwarding state causing spanning tree loops in the network. Enable loop guard on a port that transitions to the Loop-Inconsistent state until it receives BPDUs using the spanning-tree guard loop command. After BPDUs are received, the port moves out of the LoopInconsistent (or blocking) state and transitions to an appropriate state determined by STP. Enabling loop guard on a per-port basis enables it on all VLANs configured on the port. If you disable loop guard on a port, it moves to the Listening state. If you enable BPDU Filter and BPDU Guard on the same port, the BPDU Filter configuration takes precedence. Root Guard and Loop Guard are mutually exclusive. Configuring one overwrites the other from the active configuration. 1 Enable spanning-tree BPDU filter in INTERFACE mode. spanning-tree bpdufilter enable • To shut down the port channel interface, all member ports are disabled in the hardware. • To add a physical port to a port-channel already in the Error Disable state, the new member port is also disabled in the hardware. • To remove a physical port from a port-channel in Error Disable state, the Error Disabled state clears on this physical port (the physical port is enabled in the hardware). 216 Layer 2