Dell S4048-ON, Configuration Manual

Page: 551 / 1039

To view the current values for these interface parameters, use the
show config
command from INTERFACE mode.
Configuring an EdgePort
The EdgePort feature enables interfaces to begin forwarding traffic approximately 30 seconds sooner.
In this mode, an interface forwards frames by default until it receives a BPDU that indicates that it should behave otherwise; it does
not go through the Learning and Listening states. The
bpduguard shutdown-on-violation
option causes the interface
hardware to be shut down when it receives a BPDU. When you implement only
bpduguard
, although the interface is placed in an
Error Disabled state when receiving the BPDU, the physical interface remains up and spanning-tree drops packets in the hardware
after a BPDU violation. BPDUs are dropped in the software after receiving the BPDU violation. This feature is the same as PortFast
mode in spanning tree.
CAUTION: Configure EdgePort only on links connecting to an end station. EdgePort can cause loops if you enable it on
an interface connected to a network.
To enable EdgePort on an interface, use the following command.
• Enable EdgePort on an interface.
INTERFACE mode
spanning-tree mstp edge-port [bpduguard | shutdown-on-violation]
Dell Networking OS Behavior : Regarding
bpduguard shutdown-on-violation
behavior:
– If the interface to be shut down is a port channel, all the member ports are disabled in the hardware.
– When you add a physical port to a port channel already in the Error Disable state, the new member port is also disabled in the
hardware.
– When you remove a physical port from a port channel in the Error Disable state, the error disabled state is cleared on this
physical port (the physical port is enabled in the hardware).
– The reset linecard command does not clear the Error Disabled state of the port or the Hardware Disabled state. The
interface continues to be disabled in the hardware.
– You can clear the Error Disabled state with any of the following methods:
* Use the
shutdown
command on the interface.
* Disable the
shutdown-on-violation
command on the interface (using the
no spanning-tree stp-id
portfast [bpduguard | [shutdown-on-violation]]
command).
* Disable spanning tree on the interface (using the
no spanning-tree
command in INTERFACE mode).
* Disabling global spanning tree (using the
no spanning-tree
command in CONFIGURATION mode).
Example of Enabling an EdgePort on an Interface
To verify that EdgePort is enabled, use the
show config
command from INTERFACE mode.
Dell(conf-if-te-3/11)#spanning-tree mstp edge-port
Dell(conf-if-te-3/11)#show config
!
interface TenGigabitEthernet 3/11
no ip address
switchport
spanning-tree mstp edge-port
spanning-tree MSTI 1 priority 144
no shutdown
Dell(conf-if-te-3/11)#
Flush MAC Addresses after a Topology Change
Dell Networking OS has an optimized MAC address flush mechanism for RSTP, MSTP, and PVST+ that flushes addresses only when
necessary, which allows for faster convergence during topology changes.
However, you may activate the flushing mechanism defined by 802.1Q-2003 using the
tc-flush-standard
command, which
flushes MAC addresses after every topology change notification.
Multiple Spanning Tree Protocol (MSTP)
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