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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter18 Configuring MSTP Configuring MSTP Features
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 i s con s ide red t o have a share d
connection. If you have a half-duplex link physically connected point-to-point to a single port on a
remote switch running MSTP, you can override the default setting of the link type and enable rapid
transitions to the forwarding state.
Beginning in privileged EXEC mode, follow these steps to override the default link-type s ett ing. Thi s
procedure is optional.
To return the port to its default setting, use the no spanning-tree link-type interface configuration
command.
Designating the Neighbor Type
A topology could contain both prestandard and IEEE 802 .1s st anda rd com pl iant devices. By defau lt,
ports can automatically detect prestandard devices, but they can still r ece ive both sta nda rd a nd
prestandard BPDUs. When there is a mismatch between a device a nd i ts ne igh bor, only th e CIST r uns
on the interface.
You can choose to set a port to send only prestandard BPDUs. The prestandard flag a ppea rs in all th e
show commands, even if the port is in STP compatibility mode.
Beginning in privileged EXEC mode, follow these steps to override the default link-type s ett ing. Thi s
procedure is optional.
To return the port to its default setting, use the no spanning-tree mst prestandard interface
configuration command.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify an interface to configure, and enter interface
configuration mode. Valid interfaces include physical ports,
VLANs, and port-channel logical interfaces. The VLAN ID
range is 1 to 4094. The port-channel range is 1 to 48.
Step3 spanning-tree link-type point-to-point Specify that the link type of a port is point-to-point.
Step4 end Return to privileged EXEC mode.
Step5 show spanning-tree mst interface interface-id Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify an interface to configure, and enter interface
configuration mode. Valid interfaces include physical ports.
Step3 spanning-tree mst pre-standard Specify that the port can send only prestandard BPDUs.
Step4 end Return to privileged EXEC mode.
Step5 show spanning-tree mst interface interface-id Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.