Configuring Flex Links - Cisco WS-C3020 Software Configuration Manual

Configuring Flex Links and MAC Address-Table Move Update
Command
Step 3
switchport backup interface interface-id prefer vlan
vlan-range
Step 4
end
Step 5 show interfaces [interface-id] switchport backup
Step 6 copy running-config startup config
In this 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, Gi0/8 forwards traffic for VLANs 60 and 100 to 120 and Gi0/6 forwards
traffic for VLANs 1 to 50.
Switch#show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface
------------------------------------------------------------------------
GigabitEthernet0/6
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 Gi0/6 goes down, Gi0/8 carries
all VLANs of the Flex Link pair.
Switch#show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface
------------------------------------------------------------------------
GigabitEthernet0/6
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 Gi0/6 comes up, VLANs preferred on this interface are blocked on the peer interface Gi0/8 and
forwarded on Gi0/6.
Switch#show interfaces switchport backup
Switch Backup Interface Pairs:
Active Interface
------------------------------------------------------------------------
GigabitEthernet0/6
Vlans Preferred on Active Interface: 1-50
Vlans Preferred on Backup Interface: 60, 100-120
Cisco Catalyst Blade Switch 3020 for HP Software Configuration Guide
19-8
Chapter 19 Configuring Flex Links and the MAC Address-Table Move Update Feature
Purpose
Configure a physical Layer 2 interface (or port channel)
as part of a Flex Links pair with the interface, and specify
the VLANs carried on the interface. The VLAN ID range
is 1 to 4094.
Return to privileged EXEC mode.
Verify the configuration.
(Optional) Save your entries in the switch startup
configuration file.
Backup Interface
GigabitEthernet0/8 Active Up/Backup Standby
Backup Interface
GigabitEthernet0/8 Active Down/Backup Up
Backup Interface
GigabitEthernet0/8 Active Up/Backup Standby
State
State
State
OL-8915-03