Enabling Cross-Stack Uplinkfast - Cisco Catalyst 3550 series Software Configuration Manual

Chapter 18 Configuring Optional Spanning-Tree Features

Enabling Cross-Stack UplinkFast

Before enabling CSUF, make sure your stack switches are properly connected. For more information,
see the
The CSUF feature is supported only when the switch is running PVST+. It is not supported when the
switch is running rapid PVST+ or MSTP.
Beginning in privileged EXEC mode, follow these steps to enable CSUF. This procedure is optional.
Command
Step 1 configure terminal
Step 2
spanning-tree uplinkfast [max-update-rate
pkts-per-second]
Step 1
interface interface-id
Step 2
spanning-tree stack-port
Step 3
end
Step 4 show running-config
Step 5
copy running-config startup-config
To disable CSUF on an interface, use the no spanning-tree stack-port interface configuration
command. To disable UplinkFast on the switch and all its VLANs, use the no spanning-tree uplinkfast
global configuration command.
78-11194-09
"Connecting the Stack Ports" section on page 18-8.
Purpose
Enter global configuration mode.
Enable UplinkFast on the switch.
(Optional) For max-update-rate pkts-per-second, specify the
number of packets per second at which update packets are sent. The
range is 0 to 65535; the default is 150 packets per second.
Enter interface configuration mode, and specify the GBIC interface
on which to enable CSUF.
Enable CSUF on only one stack-port GBIC interface.
The stack port connects to the GigaStack GBIC multidrop
backbone. If you try to enable CSUF on a Fast Ethernet or a
Gigabit-capable 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.
Use this command only on access switches.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Catalyst 3550 Multilayer Switch Software Configuration Guide
Configuring Optional Spanning-Tree Features
18-19