Cisco Systems 3750E Configuring Enhanced Object Tracking, Understanding Enhanced Object Tracking

Chapter 40 Configuring HSRP and Enhanced Object Tracking

Configuring Enhanced Object Tracking

This is a an example of output from the show standby privileged EXEC command, displaying HSRP information for two standby groups (group 1 and group 100):

Switch# show standby

VLAN1 - Group 1

Local state is Standby, priority 105, may preempt

Hellotime 3 holdtime 10

Next hello sent in 00:00:02.182

Hot standby IP address is 172.20.128.3 configured

Active router is 172.20.128.1 expires in 00:00:09

Standby router is local

Standby virtual mac address is 0000.0c07.ac01

Name is bbb

VLAN1 - Group 100

Local state is Active, priority 105, may preempt

Hellotime 3 holdtime 10

Next hello sent in 00:00:02.262

Hot standby IP address is 172.20.138.51 configured

Active router is local

Standby router is unknown expired

Standby virtual mac address is 0000.0c07.ac64

Name is test

Configuring Enhanced Object Tracking

HSRP has a mechanism for tracking the interface line-protocol state. The enhanced object tracking feature separates the tracking mechanism from HSRP. It creates a separate, standalone tracking process that can be used by processes other than HSRP. This feature allows tracking of 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. Several clients can track the same object, and can take different actions when the object changes state. This feature increases the availability and speed of recovery of a router system and decreases outages and outage duration.

For more information about enhanced object tracking and the commands used to configure it, see this URL:

http://www.cisco.com/en/US/products/sw/iosswrel/ps1839/products_feature_guide09186a00801541be

.html

Understanding Enhanced Object Tracking

Each tracked object has a unique number that is specified on 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.

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.

	Catalyst 3750-E and 3560-E Switch Software Configuration Guide
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