Cisco FlexLink Configuration Examples

Here you can find some configuration examples for the Cisco Flexlink.

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        Backup Interface        State
------------------------------------------------------------------------
FastEthernet1/1         FastEthernet1/2         Active Up/Backup Standby
FastEthernet1/3         FastEthernet1/4         Active Up/Backup Standby
Port-channel1           GigabitEthernet1/1      Active Up/Backup Standby

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     Backup Interface     State
------------------------------------------------------------------------
GigabitEthernet1/21     GigabitEthernet1/2     Active Down/Backup Down

Interface Pair : Gi1/21, Gi1/2
Preemption Mode : forced
Preemption Delay : 50 seconds
Bandwidth : 10000 Kbit (Gi1/1), 10000 Kbit (Gi1/2)
Mac Address Move Update Vlan : auto

To configure VLAN load balancing on Flex Links,  follow these steps:
In this example, VLANs 1 to 50, 60, and 100 to 120 are configured on the  switch:

Switch(config)# interface fastethernet 1/6
Switch(config-if)# switchport backup interface fastethernet 1/0/8 prefer vlan 60,100-120

When both interfaces are up, Fast Ethernet port1/0/8 forwards traffic for VLANs 60 and 100 to 120 and Fast Ethernet port 1/0/6 forwards traffic for VLANs 1 to 50

Switch# show interfaces switchport backup

Switch Backup Interface Pairs:

Active Interface     Backup Interface     State
------------------------------------------------------------------------
FastEthernet1/6     FastEthernet1/8     Active Up/Backup Standby

Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120