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Cisco IE 3010 Switch Software Configuration Guide
OL-23145-01
Chapter 20 Configuring Flex Links and the MAC Address-Table Move Update Feature
Configuring Flex Links and the MAC Address-Table Move Update
To disable the VLAN load balancing feature, use the no switchport backup interface interface-id
prefer vlan vlan-range interface configuration command.
In the following example, VLANs 1 to 50, 60, and 100 to 120 are configured on the switch:
Switch(config)# interface gigabitethernet 0/6
Switch(config-if)# switchport backup interface gigabitethernet 0/8 prefer vlan 60,100-120
When both interfaces are up, GigabitEthernet0/8 forwards traffic for VLANs 60 and 100 to 120, and
GigabitEthernet forwards traffic for VLANs 1 to 50.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
GigabitEthernet0/6 GigabitEthernet0/8 Active Up/Backup Standby
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
When a Flex Link interface goes down (LINK_DOWN), VLANs preferred on this interface are moved
to the peer interface of the Flex Link pair. In this example, if interface Gigabit Ethernet goes down,
Gigabit Ethernet carries all VLANs of the Flex Link pair.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
GigabitEthernet0/6 GigabitEthernet0/8 Active Down/Backup Up
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
When a Flex Link 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 Ethernet0/6 comes up, VLANs preferred on this interface are blocked on the peer
interface Gigabit Ethernet0/8 and forwarded on Gigabit Ethernet0/6.
Switch# show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface Backup Interface State
------------------------------------------------------------------------
GigabitEthernet0/6 GigabitEthernet0/8 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
------------------------------------------------------------------------
FastEthernet0/3 FastEthernet0/4 Active Down/Backup Up
Step 5 show interfaces [interface-id] switchport backup Verify the configuration.
Step 6 copy running-config startup config (Optional) Save your entries in the switch startup
configuration file.
Command Purpose