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Catalyst 2360 Switch Software Configuration Guide
OL-19808-01
Chapter 26 Configuring EtherChannels and Link-State Tracking
Understanding Link-State Tracking
You can clear PAgP channel-group information and traffic counters by using the
clear pagp
{
channel-group-number
counters
|
counters
} privileged EXEC command.
You can clear LACP channel-group information and traffic counters by using the
clear lacp
{
channel-group-number
counters
|
counters
} privileged EXEC command.
For detailed information about the fields in the displays, see the command reference for this release.
Understanding Link-State Tracking
Link-state tracking, also known as trunk failover, is a feature that binds the link state of multiple
interfaces. Link-state tracking provides redundancy in the network when used with server network
interface card (NIC) adapter teaming. When the server network adapters are configured in a primary or
secondary relationship known as
teaming
and the link is lost on the primary interface, connectivity
transparently changes to the secondary interface.
shows a network configured with link-state tracking. To enable link-state
tracking, create a
link-state group
, and specify the interfaces that are assigned to the link-state group.
An interface can be an aggregation of ports (an EtherChannel), a single physical port in access or trunk
mode, or a routed port. In a link-state group, these interfaces are bundled together. The
downstream
interfaces
are bound to the
upstream interfaces
. Interfaces connected to servers are referred to as
downstream
interfaces, and interfaces connected to distribution switches and network devices are
referred to as
upstream
interfaces.