Cisco Catalyst 4500 series Administration Manual page 681

Chapter 23 Configuring Flex Links and MAC Address-Table Move Update
To disable a Flex Links backup interface, enter the no switchport backup interface interface-id
interface configuration command.
This example shows how to configure an interface with a backup interface and to verify the
configuration:
Switch# configure terminal
Switch(conf)# interface fastethernet1/1
Switch(conf-if)# switchport backup interface fastethernet1/2
Switch(conf-if)# end
Switch# show interface switchport backup
Switch Backup Interface Pairs:
Active Interface
------------------------------------------------------------------------
FastEthernet1/1
FastEthernet1/3
Port-channel1
To configure a preemption scheme for a pair of Flex Links, perform this task:
Command
Step 1
Switch# configure terminal
Step 2
Switch(conf)# interface interface-id
Step 3
Switch(conf-if)# switchport backup interface
interface-id
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
OL_28731-01
Backup Interface
FastEthernet1/2
FastEthernet1/4
GigabitEthernet1/1
Purpose
Enters global configuration mode.
Specifies the interface, and enters interface configuration
mode. The interface might be a physical Layer 2 interface
or a port channel (logical interface). The port channel
range is 1 to 64.
Configures a physical Layer 2 interface (or port channel)
as part of a Flex Links pair with the interface. When one
link is forwarding traffic, the other interface is in standby
mode.
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.
Software Configuration Guide—Release IOS XE 3.6.0E and IOS 15.2(2)E
State
Active Up/Backup Standby
Active Up/Backup Standby
Active Up/Backup Standby
Configuring Flex Links
23-7