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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 24 Configuring FlexLinks and the MAC Address-Table Move Update
Configuration Examples for the FlexLinks and MAC Address-Table Move Update
Configuring VLAN Load Balancing on FlexLinks: Examples
In the following example, VLANs 1 to 50, 60, and 100 to 120 are configured on the switch:
Switch(config)# interface gigabitEthernet 1/2
Switch(config-if)# switchport backup interface gigabitEthernet 1/2 prefer vlan 60,100-120
When both interfaces are up, GigabitEthernet1/1 forwards traffic for VLANs 60 and 100 to 120, and
GigabitEthernet1/2 forwards traffic for VLANs 1 to 50.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
GigabitEthernet1/1 GigabitEthernet1/2 Active Up/Backup Standby
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
When a FlexLinks interface goes down (LINK_DOWN), VLANs preferred on this interface are moved
to the peer interface of the FlexLinks pair. In this example, if interface Gigabit Ethernet1/1 goes down,
Gigabit Ethernet1/2 carries all VLANs of the FlexLinks pair.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
GigabitEthernet1/1 GigabitEthernet1/2 Active Down/Backup Up
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
When a FlexLinks interface comes up, VLANs preferred on this interface are blocked on the peer
interface and moved to the forwarding state on the interface that has just come up. In this example, if
interface Gigabit Ethernet1/1 comes up, VLANs preferred on this interface are blocked on the peer
interface Gigabit Ethernet1/2 and forwarded on Gigabit Ethernet1/1.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
GigabitEthernet1/1 GigabitEthernet1/2 Active Down/Backup Up
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
Switch# show interfaces switchport backup detail
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
FastEthernet1/3 FastEthernet1/4 Active Down/Backup Up
Vlans Preferred on Active Interface: 1-2,5-4096
Vlans Preferred on Backup Interface: 3-4
Preemption Mode : off
Bandwidth : 10000 Kbit (Fa1/3), 100000 Kbit (Fa1/4)
Mac Address Move Update Vlan : auto