Installation guide

Spanning Tree Commands
4-233
4
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• When enabled, BPDUs are flooded to all other ports on the switch or to all
other ports within the receiving port’s native VLAN as specified by the
spanning-tree system-bpdu-flooding command (page 4-223).
•The spanning-tree system-bpdu-flooding command has no effect if BPDU
flooding is disabled on a port by the spanning-tree port-bpdu-flooding
command.
Example
spanning-tree link-type
This command configures the link type for Rapid Spanning Tree and Multiple
Spanning Tree. Use the no form to restore the default.
Syntax
spanning-tree link-type {auto | point-to-point | shared}
no spanning-tree link-type
• auto - Automatically derived from the duplex mode setting.
• point-to-point - Point-to-point link.
• shared - Shared medium.
Default Setting
auto
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• Specify a point-to-point link if the interface can only be connected to exactly
one other bridge, or a shared link if it can be connected to two or more bridges.
• When automatic detection is selected, the switch derives the link type from the
duplex mode. A full-duplex interface is considered a point-to-point link, while
a half-duplex interface is assumed to be on a shared link.
• RSTP only works on point-to-point links between two bridges. If you designate
a port as a shared link, RSTP is forbidden. Since MSTP is an extension of
RSTP, this same restriction applies.
Example
Console(config)#interface ethernet 1/5
Console(config-if)#spanning-tree port-bpdu-flooding
Console(config-if)#
Console(config)#interface ethernet 1/5
Console(config-if)#spanning-tree link-type point-to-point
Console(config-if)#