Chapter 17
| Spanning Tree Commands
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◆
When edge port is set as auto, the operational state is determined
automatically by the Bridge Detection State Machine described in 802.1D-
2004, where the edge port state may change dynamically based on
environment changes (e.g., receiving a BPDU or not within the required
interval).
Example
Console(config)#interface ethernet 1/5
Console(config-if)#spanning-tree edge-port
Console(config-if)#
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 link-type point-to-point
