D-Link DGS-1250 Emulator - Page 460

spanning-tree link-type

Page 460 highlights

DGS-1250 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide spanning-tree guard root no spanning-tree guard root Parameters None. Default By default, this option is disabled. Command Mode Interface Configuration Mode. Usage Guideline BPDU guard prevents a port from becoming a root port. This feature is useful for the service provider to prevent external bridges to a core region of the network influencing the spanning tree active topology, possibly because those bridges are not under the full control of the administrator. When a port is guarded from becoming a root port, the port will only play the role as a designated port. If the port receives the configuration BPDU with a higher priority, the port will change to the alternate port, which is in the blocking state. The received superior factor will not participate in the STP computation. The port will listen for BPDUs on the link. If the port times out the received superior BPDU, it will change to the designated port role. When a port changes to the alternate port state, due to the root guard, a system message will be generated. This configuration will take effect for all the spanning-tree versions. Example This example shows how to configure to prevent port 1 from being a root port. Switch# configure terminal Switch(config)# interface eth1/0/1 Switch(config-if)# spanning-tree guard root Switch(config-if)# 58-10 spanning-tree link-type This command is used to configure a link-type for a port. Use the no form of this command to revert to the default setting. spanning-tree link-type {point-to-point | shared} no spanning-tree link-type Parameters point-to-point shared Specifies that the port's link type is point-to-point. Specifies that the port's link type is a shared media connection. Default The link type is automatically derived from the duplex setting unless explicitly configuring the link type. Command Mode Interface Configuration Mode. 457

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DGS-1250 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide
457
spanning-tree guard root
no spanning-tree guard root
Parameters
None.
Default
By default, this option is disabled.
Command Mode
Interface Configuration Mode.
Usage Guideline
BPDU guard prevents a port from becoming a root port. This feature is useful for the service provider to prevent
external bridges to a core region of the network influencing the spanning tree active topology, possibly because
those bridges are not under the full control of the administrator.
When a port is guarded from becoming a root port, the port will only play the role as a designated port. If the port
receives the configuration BPDU with a higher priority, the port will change to the alternate port, which is in the
blocking state. The received superior factor will not participate in the STP computation. The port will listen for
BPDUs on the link. If the port times out the received superior BPDU, it will change to the designated port role.
When a port changes to the alternate port state, due to the root guard, a system message will be generated. This
configuration will take effect for all the spanning-tree versions.
Example
This example shows how to configure to prevent port 1 from being a root port.
Switch# configure terminal
Switch(config)# interface eth1/0/1
Switch(config-if)# spanning-tree guard root
Switch(config-if)#
58-10 spanning-tree link-type
This command is used to configure a link-type for a port. Use the
no
form of this command to revert to the default
setting.
spanning-tree link-type {point-to-point | shared}
no spanning-tree link-type
Parameters
point-to-point
Specifies that the port’s link type is point
-to-point.
shared
Specifies that the port’s link
type is a shared media connection.
Default
The link type is automatically derived from the duplex setting unless explicitly configuring the link type.
Command Mode
Interface Configuration Mode.