Spanning-Tree Stack-Port - Cisco Catalyst 3550 Command Reference Manual

spanning-tree stack-port

spanning-tree stack-port
Use the spanning-tree stack-port interface configuration command to enable cross-stack UplinkFast
(CSUF) on an interface and to accelerate the choice of a new root port when a link or switch fails or when
spanning tree reconfigures itself. Use the no form of this command to return to the default setting.
Syntax Description
This command has no arguments or keywords.
Defaults
CSUF is disabled on all interfaces.
Command Modes
Interface configuration
Command History Release
12.1(4)EA1
Usage Guidelines
This command is effective only if you enable the UplinkFast feature by using the spanning-tree
uplinkfast global configuration command.
Use this command only on access switches.
The CSUF feature is supported only when the switch is running per-VLAN spanning-tree plus (PVST+).
It is not supported when the switch is running rapid PVST+ or multiple spanning tree (MST).
You can enable CSUF only on one stack-port Gigabit Interface Converter (GBIC) interface. The stack
port connects to the GigaStack GBIC multidrop backbone. If you try to enable CSUF on a Fast Ethernet
or a copper-based Gigabit Ethernet port, you receive an error message.
If CSUF is already enabled on an interface and you try to enable it on another interface, you receive an
error message. You must disable CSUF on the first interface before enabling it on a new interface.
Examples
This example shows how to enable CSUF on the GBIC interface:
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# spanning-tree stack-port
You can verify your settings by entering the show running-config privileged EXEC command.
Catalyst 3550 Multilayer Switch Command Reference
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spanning-tree stack-port
no spanning-tree stack-port
Modification
This command was first introduced.
Chapter 2 Cisco IOS Commands
78-11195-09