Cisco Catalyst 3560-X Series, Software Configuration Manual

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C H A P T E R
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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-25303-03
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Configuring Enhanced Object Tracking
This chapter describes how to configure enhanced object tracking on the Catalyst 3750-X or 3560-X
switch. This feature provides a more complete alternative to the Hot Standby Routing Protocol (HSRP)
tracking mechanism. which allows you to track the line-protocol state of an interface. If the line protocol
state of an interface goes down, the HSRP priority of the interface is reduced and another HSRP device
with a higher priority becomes active. The enhanced object tracking feature separates the tracking
mechanism from HSRP and creates a separate, standalone tracking process that can be used by processes
other than HSRP. This allows tracking other objects in addition to the interface line-protocol state. A
client process, such as HSRP, can register an interest in tracking objects and request notification when
the tracked object changes state.This feature increases the availability and speed of recovery of a routing
system and decreases outages and outage duration.
Note Enhanced object tracking is not supported on switches running the LAN base feature set.
Unless otherwise noted, the term switch refers to a Catalyst 3750-X or 3560-X standalone switch and to
a Catalyst 3750-X switch stack.
The chapter includes these sections:
• Understanding Enhanced Object Tracking, page 1-1
•
Configuring Enhanced Object Tracking Features, page 1-2
• Monitoring Enhanced Object Tracking, page 1-12
Understanding Enhanced Object Tracking
Each tracked object has a unique number that is specified in the tracking command-line interface (CLI).
Client processes use this number to track a specific object. The tracking process periodically polls the
tracked object for value changes and sends any changes (as up or down values) to interested client
processes, either immediately or after a specified delay. Several clients can track the same object, and
can take different actions when the object changes state.
You can also track a combination of objects in a list by using either a weight threshold or a percentage
threshold to measure the state of the list. You can combine objects using Boolean logic. A tracked list
with a Boolean “AND” function requires that each object in the list be in an up state for the tracked object
to be up. A tracked list with a Boolean “OR” function needs only one object in the list to be in the up
state for the tracked object to be up.