Filter
Top Products
19-8
Catalyst 2960 and 2960-S Switch Software Configuration Guide
OL-8603-09
Chapter 19 Configuring Flex Links and the MAC Address-Table Move Update Feature
Configuring Flex Links and the MAC Address-Table Move Update
Default Configuration
The Flex Links are not configured, and there are no backup interfaces defined.
The preemption mode is off.
The preemption delay is 35 seconds.
The MAC address-table move update feature is not configured on the switch.
Configuration Guidelines
Follow these guidelines to configure Flex Links:
• You can configure up to 16 backup links.
• You can configure only one Flex Link backup link for any active link, and it must be a different
interface from the active interface.
• An interface can belong to only one Flex Link pair. An interface can be a backup link for only one
active link. An active link cannot belong to another Flex Link pair.
• Neither of the links can be a port that belongs to an EtherChannel. However, you can configure two
port channels (EtherChannel logical interfaces) as Flex Links, and you can configure a port channel
and a physical interface as Flex Links, with either the port channel or the physical interface as the
active link.
• A backup link does not have to be the same type (Fast Ethernet, Gigabit Ethernet, or port channel)
as the active link. However, you should configure both Flex Links with similar characteristics so that
there are no loops or changes in behavior if the standby link begins to forward traffic.
• STP is disabled on Flex Link ports. A Flex Link port does not participate in STP, even if the VLANs
present on the port are configured for STP. When STP is not enabled, be sure that there are no loops
in the configured topology. Once the Flex Link configurations are removed, STP is re-enabled on
the ports.
Follow these guidelines to configure VLAN load balancing on the Flex Links feature:
• For Flex Link VLAN load balancing, you must choose the preferred VLANs on the backup interface.
• You cannot configure a preemption mechanism and VLAN load balancing for the same Flex Links
pair.
Follow these guidelines to configure the MAC address-table move update feature:
• You can enable and configure this feature on the access switch to send the MAC address-table move
updates.
• You can enable and configure this feature on the uplink switches to receive the MAC address-table
move updates.