Specifying The Link Type; Restarting The Protocol; Verifying Rapid Pvst+ Configurations - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Specifying the Link Type

Specifying the Link Type
Rapid connectivity (802.1w standard) is established only on point-to-point links. By default, the link type is
controlled from the duplex mode of the interface. A full-duplex port is considered to have a point-to-point
connection; a half-duplex port is considered to have a shared connection.
If you have a half-duplex link physically connected point-to-point to a single port on a remote switch, you
can override the default setting on the link type and enable rapid transitions.
If you set the link to shared, STP moves back to 802.1D.
Procedure
Step 1
Step 2
Step 3
This example shows how to configure the link type as a point-to-point link:
switch# configure terminal
switch (config)# interface ethernet 1/4
switch(config-if)# spanning-tree link-type point-to-point
You can only apply this command to a physical Ethernet interface.

Restarting the Protocol

A bridge running Rapid PVST+ can send 802.1D BPDUs on one of its ports when it is connected to a legacy
bridge. However, the STP protocol migration cannot determine whether the legacy switch has been removed
from the link unless the legacy switch is the designated switch. You can restart the protocol negotiation (force
the renegotiation with neighboring switches) on the entire switch or on specified interfaces.
Command
switch# clear spanning-tree detected-protocol
[interface interface [interface-num | port-channel]]
The following example shows how to restart Rapid PVST+ on an Ethernet interface:
switch# clear spanning-tree detected-protocol interface ethernet 1/8

Verifying Rapid PVST+ Configurations

To display Rapid PVST+ configuration information, perform one of these tasks:
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
172
Command or Action
switch# configure terminal
switch(config)# interface type
slot/port
switch(config-if)# spanning-tree
link-type {auto | point-to-point |
shared}
Verifying Rapid PVST+ Configurations
Purpose
Enters configuration mode.
Specifies the interface to configure, and enters the interface
configuration mode.
Configures the link type to be either a point-to-point link or
shared link. The system reads the default value from the
switch connection, as follows: half duplex links are shared
and full-duplex links are point-to-point. If the link type is
shared, the STP reverts to 802.1D. The default is auto, which
sets the link type based on the duplex setting of the interface.
Purpose
Restarts Rapid PVST+ on all interfaces on the switch
or specified interfaces.
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