Cisco Catalyst 4500 Series Software Configuration Manual page 751

Chapter 24 Configuring Flex Links and MAC Address-Table Move Update
Command
Step 4
Switch(conf-if)# switchport backup interface
interface-id preemption mode [forced | bandwidth
| off]
Step 5
Switch(conf-if)# switchport backup interface
interface-id preemption delay delay-time
Step 6
Switch(conf)# end
Step 7
Switch# show interface [interface-id] switchport
backup
Step 8
Switch# copy running-config startup config
To remove a preemption scheme, enter the no switchport backup interface interface-id preemption
mode interface configuration command. To reset the delay time to the default, enter the
no switchport backup interface interface-id preemption delay interface configuration command.
This example shows how to configure preemption mode as bandwidth for a backup interface pair and to
verify the configuration:
Switch# configure terminal
Switch(conf)# interface gigabitethernet1/0/1
Switch(conf-if)# switchport backup interface gigabitethernet1/2
Switch(conf-if)# switchport backup interface gigabitethernet1/2 preemption mode forced
Switch(conf-if)# switchport backup interface gigabitethernet1/2 preemption delay 50
Switch(conf-if)# end
Switch# show interface switchport backup detail
Active Interface
------------------------------------------------------------------------
GigabitEthernet1/21
Interface Pair
Preemption Mode
Preemption Delay : 50 seconds
Bandwidth : 10000 Kbit (Gi1/1), 10000 Kbit (Gi1/2)
Mac Address Move Update Vlan : auto
<output truncated>
Backup Interface
GigabitEthernet1/2
: Gi1/21, Gi1/2
: forced
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Purpose
Configures a preemption mechanism and delay for a Flex
Links interface pair. You can configure the preemption
mode as:
forced—The active interface always preempts the
•
backup.
bandwidth—The interface with higher bandwidth
•
always acts as the active interface.
off—No preemption occurs from active to backup.
•
Configures the delay time until a port preempts another
port.
Setting a delay time requires forced or bandwidth
Note
mode.
Returns to privileged EXEC mode.
Verifies the configuration.
(Optional) Saves your entries in the switch startup
configuration file.
State
Active Down/Backup Down
Configuring Flex Links
24-7