Configuring Enhanced Object Tracking

First Published: May 2, 2005
Last Updated: July 1, 2009

Before the introduction of the Enhanced Object Tracking feature, the Hot Standby Router Protocol (HSRP) had a simple tracking mechanism that allowed you to track the interface line-protocol state only. If the line-protocol state of the interface went down, the HSRP priority of the router was reduced, allowing another HSRP router with a higher priority to become active.

The Enhanced Object Tracking feature separates the tracking mechanism from HSRP and creates a separate standalone tracking process that can be used by other Cisco IOS XE processes as well as HSRP. This feature allows tracking of other objects in addition to the interface line-protocol state.

A client process, such as HSRP, Virtual Router Redundancy Protocol (VRRP), or Gateway Load Balancing Protocol (GLBP), can now register its interest in tracking objects and then be notified when the tracked object changes state.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the "Feature Information for Enhanced Object Tracking" section.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Contents

•Information About Enhanced Object Tracking

•How to Configure Enhanced Object Tracking

•Configuration Examples for Enhanced Object Tracking

•Additional References

•Feature Information for Enhanced Object Tracking

•Glossary

Information About Enhanced Object Tracking

Before you configure the Enhanced Object Tracking feature, you should understand the following concepts:

•Feature Design of Enhanced Object Tracking

•Enhanced Object Tracking and Embedded Event Manager

•IP-Routing State of an Interface

•IP-Routing State of an Interface

•Tracking IP SLAs Operations

•IP-Routing State of an Interface

Feature Design of Enhanced Object Tracking

Enhanced Object Tracking provides complete separation between the objects to be tracked and the action to be taken by a client when a tracked object changes. Thus, several clients such as HSRP, VRRP, or GLPB can register their interest with the tracking process, track the same object, and each take different action when the object changes.

Each tracked object is identified by 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 objects and notes any change of value. The changes in the tracked object are communicated to interested client processes, either immediately or after a specified delay. The object values are reported as either up or down.

You can also configure a combination of tracked objects in a list and a flexible method for combining objects using Boolean logic. This functionality includes the following capabilities:

•Threshold—The tracked list can be configured to use a weight or percentage threshold to measure the state of the list. Each object in a tracked list can be assigned a threshold weight. The state of the tracked list is determined by whether or not the threshold has been met.

•Boolean "and" function—When a tracked list has been assigned a Boolean "and" function, it means that each object defined within a subset must be in an up state so that the tracked object can become up.

•Boolean "or" function—When the tracked list has been assigned a Boolean "or" function, it means that at least one object defined within a subset must be in an up state so that the tracked object can become up.

Enhanced Object Tracking and Embedded Event Manager

Enhanced Object Tracking (EOT) is now integrated with Embedded Event Manager (EEM) to allow EEM to report on status change of a tracked object and to allow EOT to track EEM objects. A new type of tracking object—a stub object—is created. The stub object can be modified by an external process through a defined Application Programming Interface (API). See the "Embedded Event Manager Overview" document in the Cisco IOS XE Network Management Configuration Guide for more information on how EOT works with EEM.

IP-Routing State of an Interface

An IP-routing object is considered up when the following criteria exist:

•IP routing is enabled and active on the interface.

•The interface line-protocol state is up.

•The interface IP address is known. The IP address is configured or received through the Dynamic Host Configuration Protocol (DHCP) or IP Control Protocol (IPCP) negotiation.

Interface IP routing will go down when one of the following criteria exist:

•IP routing is disabled globally.

•The interface line-protocol state is down.

•The interface IP address is unknown. The IP address is not configured or received through DHCP or IPCP negotiation.

Tracking the IP-routing state of an interface using the track interface ip routing command can be more useful in some situations than just tracking the line-protocol state using the track interface line-protocol command, especially on interfaces for which IP addresses are negotiated. For example, on a serial interface that uses the Point-to-Point Protocol (PPP), the line protocol could be up (link control protocol [LCP] negotiated successfully), but IP could be down (IPCP negotiation failed).

The track interface ip routing command supports the tracking of an interface with an IP address acquired through any of the following methods:

•Conventional IP address configuration

•PPP/IPCP

•DHCP

•Unnumbered interface

Scaled Route Metrics

The track ip route command enables tracking of a route in the routing table. If a route exists in the table, the metric value is converted into a number. To provide a common interface to tracking clients, route metric values are normalized to the range from 0 to 255, where 0 is connected and 255 is inaccessible. Scaled metrics can be tracked by setting thresholds. Up and down state notification occurs when the thresholds are crossed. The resulting value is compared against threshold values to determine the tracking state as follows:

•State is up if the scaled metric for that route is less than or equal to the up threshold.

•State is down if the scaled metric for that route is greater than or equal to the down threshold.

Tracking uses a per-protocol configurable resolution value to convert the real metric to the scaled metric. Table 1 shows the default values used for the conversion. You can use the track resolution command to change the metric resolution default values.

Table 1 Metric Conversion

Route Type 1
Metric Resolution

Static

10

Enhanced Interior Gateway Routing Protocol (EIGRP)

2560

Open Shortest Path First (OSPF)

1

Intermediate System-to-Intermediate System (IS-IS)

10

1 RIP is scaled directly to the range from 0 to 255 because its
maximum metric is less than 255.


For example, a change in 10 in an IS-IS metric results in a change of 1 in the scaled metric. The default resolutions are designed so that approximately one 2-Mbps link in the path will give a scaled metric of 255.

Scaling the very large metric ranges of EIGRP and IS-IS to a 0 to 255 range is a compromise. The default resolutions will cause the scaled metric to go above the maximum limit with a 2-Mbps link. However, this scaling allows a distinction between a route consisting of three Fast-Ethernet links and a route consisting of four Fast-Ethernet links.

Tracking IP SLAs Operations

Object tracking of IP SLAs operations allows tracking clients to track the output from IP SLAs objects and use the provided information to trigger an action.

Cisco IOS XE IP SLAs is a network performance measurement and diagnostics tool that uses active monitoring. Active monitoring is the generation of traffic in a reliable and predictable manner to measure network performance. Cisco IOS software uses IP SLAs to collect real-time metrics such as response time, network resource availability, application performance, jitter (interpacket delay variance), connect time, throughput, and packet loss.

These metrics can be used for troubleshooting, for proactive analysis before problems occur, and for designing network topologies.

Every IP SLAs operation maintains an operation return-code value. This return code is interpreted by the tracking process. The return code can return OK, OverThreshold, and several other return codes. Different operations can have different return-code values, so only values common to all operation types are used.

Two aspects of an IP SLAs operation can be tracked: state and reachability. The difference between these aspects relates to the acceptance of the OverThreshold return code. Table 2 shows the state and reachability aspects of IP SLAs operations that can be tracked.

Table 2 Comparison of State and Reachability Operations

Tracking
Return Code
Track State

State

OK

(all other return codes)

Up

Down

Reachability

OK or OverThreshold

(all other return codes)

Up

Down


Benefits of Enhanced Object Tracking

•Increases the availability and speed of recovery of a network.

•Decreases network outages and their duration.

•Provides a scalable solution that allows other client processes such as VRRP and GLBP the ability to track objects individually or as a list of objects. Prior to the introduction of this functionality, the tracking process was embedded within HSRP.

How to Configure Enhanced Object Tracking

•Tracking the Line-Protocol State of an Interface (optional)

•Tracking the IP-Routing State of an Interface (optional)

•Tracking IP-Route Reachability (optional)

•Tracking the Threshold of IP-Route Metrics (optional)

•Tracking the State of an IP SLAs Operation (optional)

•Tracking the Reachability of an IP SLAs IP Host (optional)

•Configuring a Tracked List and Boolean Expression (optional)

•Configuring a Tracked List and Threshold Weight (optional)

•Configuring a Tracked List and Threshold Percentage (optional)

•Configuring the Track List Defaults (optional)

Tracking the Line-Protocol State of an Interface

Perform this task to track the line-protocol state of an interface.

Tracking the IP-routing state of an interface using the track interface ip routing command can be more useful in some situations than just tracking the line-protocol state using the track interface line-protocol command, especially on interfaces for which IP addresses are negotiated. See the "Tracking the IP-Routing State of an Interface" section for more information.

SUMMARY STEPS

1. enable

2. configure terminal

3. track timer interface seconds

4. track object-number interface type number line-protocol

5. delay {up seconds [down seconds] | [up seconds] down seconds}

6. end

7. show track object-number

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track timer interface seconds

Example:

Router(config)# track timer interface 5

(Optional) Specifies the interval in which the tracking process polls the tracked object.

•The default interval that the tracking process polls interface objects is 1 second.

Step 4 

track object-number interface type number line-protocol

Example:

Router(config)# track 3 interface GigabitEthernet 1/0/0 line-protocol

Tracks the line-protocol state of an interface and enters tracking configuration mode.

Step 5 

delay {up seconds [down seconds]|[up seconds] down seconds}

Example:

Router(config-track)# delay up 30

(Optional) Specifies a period of time (in seconds) to delay communicating state changes of a tracked object.

Step 6 

end

Example:

Router(config-track)# end

Exits to privileged EXEC mode.

Step 7 

show track object-number

Example:

Router# show track 3

(Optional) Displays tracking information.

•Use this command to verify the configuration. See the display output in the "Examples" section.

Examples

The following example shows the state of the line protocol on an interface when it is tracked: 

Router# show track 3


Track 3

   Interface GigabitEthernet1/0/0 line-protocol

   Line protocol is Up

     1 change, last change 00:00:05

   Tracked by:

     HSRP GigabitEthernet0/0/0 3

Tracking the IP-Routing State of an Interface

SUMMARY STEPS

1. enable

2. configure terminal

3. track timer interface seconds

4. track object-number interface type number ip routing

5. delay {up seconds [down seconds] | [up seconds] down seconds}

6. end

7. show track object-number

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track timer interface seconds

Example:

Router(config)# track timer interface 5

(Optional) Specifies the interval in which the tracking process polls the tracked object.

•The default interval that the tracking process polls interface objects is 1 second.

Step 4 

track object-number interface type number ip routing

Example:

Router(config)# track 1 interface GigabitEthernet 1/0/0 ip routing

Tracks the IP-routing state of an interface and enters tracking configuration mode.

•IP-route tracking tracks an IP route in the routing table and the ability of an interface to route IP packets.

Step 5 

delay {up seconds [down seconds]|[up seconds] down seconds}

Example:

Router(config-track)# delay up 30

(Optional) Specifies a period of time (in seconds) to delay communicating state changes of a tracked object.

Step 6 

end

Example:

Router(config-track)# end

Returns to privileged EXEC mode.

Step 7 

show track object-number

Example:

Router# show track 1

Displays tracking information.

•Use this command to verify the configuration. See the display output in the "Examples" section.

Examples

The following example shows the state of IP routing on an interface when it is tracked: 

Router# show track 1


Track 1

   Interface GigabitEthernet1/0/0 ip routing

   IP routing is Up

     1 change, last change 00:01:08

   Tracked by:

     HSRP GigabitEthernet0/0/0 1

Tracking IP-Route Reachability

Perform this task to track the reachability of an IP route. A tracked object is considered up when a routing table entry exists for the route and the route is accessible.

SUMMARY STEPS

1. enable

2. configure terminal

3. track timer ip route seconds

4. track object-number ip route ip-address/prefix-length reachability

5. delay {up seconds [down seconds] | [up seconds] down seconds}

6. ip vrf vrf-name

7. end

8. show track object-number

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track timer ip route seconds

Example:

Router(config)# track timer ip route 20

(Optional) Specifies the interval in which the tracking process polls the tracked object.

•The default interval that the tracking process polls IP-route objects is 15 seconds.

Step 4 

track object-number ip route ip-address/prefix-length reachability

Example:

Router(config)# track 4 ip route 10.16.0.0/16 reachability

Tracks the reachability of an IP route and enters tracking configuration mode.

Step 5 

delay {up seconds [down seconds]|[up seconds] down seconds}

Example:

Router(config-track)# delay up 30

(Optional) Specifies a period of time (in seconds) to delay communicating state changes of a tracked object.

Step 6 

ip vrf vrf-name

Example:

Router(config-track)# ip vrf VRF2

(Optional) Configures a VPN routing and forwarding (VRF) table.

Step 7 

end

Example:

Router(config-track)# end

Returns to privileged EXEC mode.

Step 8 

show track object-number

Example:

Router# show track 4

(Optional) Displays tracking information.

•Use this command to verify the configuration. See the display output in the "Examples" section.

Examples

The following example shows the state of the reachability of an IP route when it is tracked: 

Router# show track 4


Track 4

   IP route 10.16.0.0 255.255.0.0 reachability

   Reachability is Up (RIP)

     1 change, last change 00:02:04

   First-hop interface is GigabitEthernet0/1

   Tracked by:

     HSRP GigabitEthernet1/0/3 4

Tracking the Threshold of IP-Route Metrics

SUMMARY STEPS

1. enable

2. configure terminal

3. track timer ip route seconds

4. track resolution ip route {eigrp resolution-value | isis resolution-value | ospf resolution-value | static resolution-value}

5. track object-number ip route ip-address/prefix-length metric threshold

6. delay {up seconds [down seconds] | [up seconds] down seconds}

7. ip vrf vrf-name

8. threshold metric {up number [down number] | down number [up number]}

9. end

10. show track object-number

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track timer ip route seconds

Example:

Router(config)# track timer ip route 20

(Optional) Specifies the interval in which the tracking process polls the tracked object.

•The default interval that the tracking process polls IP-route objects is 15 seconds.

Step 4 

track resolution ip route {eigrp resolution-value | isis resolution-value | ospf resolution-value | static resolution-value}

Example:

Router(config)# track resolution ip route eigrp 300

(Optional) Specifies resolution parameters for a tracked object.

•Use this command to change the default metric resolution values.

Step 5 

track object-number ip route ip-address/ prefix-length metric threshold

Example:

Router(config)# track 6 ip route 10.16.0.0/16 metric threshold

Tracks the scaled metric value of an IP route to determine if it is above or below a threshold.

•The default down value is 255, which equates to an inaccessible route.

•The default up value is 254.

Step 6 

delay {up seconds [down seconds] | [up seconds] down seconds}

Example:

Router(config-track)# delay up 30

(Optional) Specifies a period of time (in seconds) to delay communicating state changes of a tracked object.

Step 7 

ip vrf vrf-name

Example:

Router(config-track)# ip vrf VRF1

(Optional) Configures a VRF table.

Step 8 

threshold metric {up number [down number] | down number [up number]}

Example:

Router(config-track)# threshold metric up 254 down 255

(Optional) Sets a metric threshold other than the default value.

Step 9 

end

Example:

Router(config-track)# end

Exits to privileged EXEC mode.

Step 10 

show track object-number

Example:

Router# show track 6

(Optional) Displays tracking information.

•Use this command to verify the configuration. See the display output in the "Examples" section.

Examples

The following example shows the metric threshold of an IP route when it is tracked: 

Router# show track 6


Track 6

   IP route 10.16.0.0 255.255.0.0 metric threshold

   Metric threshold is Up (RIP/6/102)

     1 change, last change 00:00:08

   Metric threshold down 255 up 254

   First-hop interface is GigabitEthernet0/1/1

   Tracked by:

     HSRP GigabitEthernet1/0/0 6

Tracking the State of an IP SLAs Operation

SUMMARY STEPS

1. enable

2. configure terminal

3. track object-number rtr operation-number state
or
track object-number ip sla operation-number state

4. delay {up seconds [down seconds] | [up seconds] down seconds}

5. end

6. show track object-number

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

Cisco IOS XE Releases Prior to XE2.4

track object-number rtr operation-number state

Cisco IOS XE Release 2.4 or Later Releases

track object-number ip sla operation-number state

Example: Cisco IOS XE Releases Prior to XE2.4

Router(config)# track 2 rtr 4 state

Example: Cisco IOS XE Release 2.4 Later Releases

Router(config)# track 2 ip sla 4 state

Tracks the state of an IP SLAs object and enters tracking configuration mode.

Note Effective with Cisco IOS XE Release 2.4 the track rtr command was replaced by the track ip sla command. The track rtr command will be removed in a future release and is available only to aid the update of existing configurations to the track ip sla command.

Step 4 

delay {up seconds [down seconds] | [up seconds] down seconds}

Example:

Router(config-track)# delay up 60 down 30

(Optional) Specifies a period of time (in seconds) to delay communicating state changes of a tracked object.

Step 5 

end

Example:

Router(config-track)# end

Exits to privileged EXEC mode.

Step 6 

show track object-number

Example:

Router# show track 2

(Optional) Displays tracking information.

•Use this command to verify the configuration. See the display output in the "Examples" section of this task.

Examples

The following example shows the state of the IP SLAs tracking: 

Router# show track 2


Track 2

   IP SLA 1 state

   State is Down

     1 change, last change 00:00:47

   Latest operation return code: over threshold

   Latest RTT (millisecs) 4

   Tracked by:

     HSRP GigabitEthernet1/0/0 2

Tracking the Reachability of an IP SLAs IP Host

SUMMARY STEPS

1. enable

2. configure terminal

3. track object-number rtr operation-number reachability

or
track object-number ip sla operation-number reachability

4. delay {up seconds [down seconds] | [up seconds] down seconds}

5. end

6. show track object-number

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

Cisco IOS XE Releases Prior to 2.4:

track object-number rtr operation-number reachability

Cisco IOS XE Release 2.4 or Later Releases

track object-number ip sla operation-number reachability

Example: Cisco IOS XE Releases Prior to 2.4:

Router(config)# track 2 rtr 4 reachability

Example: Cisco IOS XE Release 2.4 or Later Releases

Router(config)# track 2 ip sla 4 reachability

Tracks the reachability of an IP SLAs IP host and enters tracking configuration mode.

Note Effective with Cisco IOS XE Release 2.4 the track rtr command was replaced by the track ip sla command. The track rtr command will be removed in a future release and is available only to aid the update of existing configurations to the track ip sla command.

Step 4 

delay {up seconds [down seconds] | [up seconds] down seconds}

Example:

Router(config-track)# delay up 30 down 10

(Optional) Specifies a period of time (in seconds) to delay communicating state changes of a tracked object.

Step 5 

end

Example:

Router(config-track)# end

Exits to privileged EXEC mode.

Step 6 

show track object-number

Example:

Router# show track 3

(Optional) Displays tracking information.

•Use this command to verify the configuration. See the display output in the "Examples" section of this task.

Examples

The following example shows whether the route is reachable: 

Router# show track 3


Track 3

   IP SLA 1 reachability

   Reachability is Up

     1 change, last change 00:00:47

   Latest operation return code: over threshold

   Latest RTT (millisecs) 4

   Tracked by:

     HSRP GigabitEthernet1/0/0 3

Configuring a Tracked List and Boolean Expression

Perform this task to configure a tracked list of objects and a Boolean expression to determine the state of the list. A tracked list contains one or more objects. The Boolean expression enables two types of calculations by using either "and" or "or" operators. For example, when tracking two interfaces using the "and" operator, up means that both interfaces are up, and down means that either interface is down.

You may also configure a tracked list state to be measured using a weight or percentage threshold. See "Configuring a Tracked List and Threshold Weight" section and "Configuring a Tracked List and Threshold Percentage" section.

Prerequisites

An object must exist before it can be added to a tracked list.

Note The "not" operator is specified for one or more objects and negates the state of the object.

SUMMARY STEPS

1. enable

2. configure terminal

3. track track-number list boolean {and | or}

4. object object-number [not]

5. delay {up seconds [down seconds] | [up seconds] down seconds}

6. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track track-number list boolean {and | or}

Example:

Router(config-track)# track 100 list boolean and

Configures a tracked list object and enters tracking configuration mode. The keywords are as follows:

•boolean—Specifies that the state of the tracked list is based on a Boolean calculation. The keywords are as follows:

–and—Specifies that the list is up if all objects are up, or down if one or more objects are down. For example when tracking two interfaces, up means that both interfaces are up, and down means that either interface is down.

–or—Specifies that the list is up if at least one object is up. For example, when tracking two interfaces, up means that either interface is up, and down means that both interfaces are down.

Step 4 

object object-number [not]

Example:

Router(config-track)# object 3 not

Specifies the object to be tracked. The object-number argument has a valid range from 1 to 500. There is no default. The optional not keyword negates the state of the object.

Note The example means that when object 3 is up, the tracked list detects object 3 as down.

Step 5 

delay {up seconds [down seconds] | [up seconds] down seconds}

Example:

Router(config-track)# delay up 3

(Optional) Specifies a tracking delay in seconds between up and down states.

Step 6 

end

Example:

Router(config-track)# end

Returns to privileged EXEC mode.

Configuring a Tracked List and Threshold Weight

Perform this task to configure a list of tracked objects, to specify that weight be used as the threshold, and to configure a weight for each of its objects. A tracked list contains one or more objects. Using a threshold weight, the state of each object is determined by comparing the total weight of all objects that are up against a threshold weight for each object.

You can also configure a tracked list state to be measured using a Boolean calculation or threshold percentage. See the "Configuring a Tracked List and Boolean Expression" section and the "Configuring a Tracked List and Threshold Percentage" section.

Prerequisites

An object must exist before it can be added to a tracked list.

Restrictions

You cannot use the Boolean "not" operator in a weight or percentage threshold list.

SUMMARY STEPS

1. enable

2. configure terminal

3. track track-number list threshold weight

4. object object-number [weight weight-number]

5. threshold weight {up number down number | up number | down number}

6. delay {up seconds [down seconds] | [up seconds] down seconds}

7. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track track-number list threshold weight

Example:

Router(config-track)# track 100 list threshold weight

Configures a tracked list object and enters tracking configuration mode. The keywords are as follows:

•threshold—Specifies that the state of the tracked list is based on a threshold.

•weight—Specifies that the threshold is based on a specified weight.

Step 4 

object object-number [weight weight-number]

Example:

Router(config-track)# object 3 weight 30

Specifies the object to be tracked. The object-number argument has a valid range from 1 to 500. There is no default. The optional weight keyword specifies a threshold weight for each object.

Step 5 

threshold weight {up number down number | up number | down number}

Example:

Router(config-track)# threshold weight up 30

Specifies the threshold weight. The keywords and arguments are as follows:

•up number—Valid range is from 1 to 255.

•down number—Range depends upon what you select for the up keyword. For example, if you configure 25 for up, you will see a range from 0 to 24 for down.

Step 6 

delay {up seconds [down seconds] | [up seconds] down seconds}

Example:

Router(config-track)# delay up 3

(Optional) Specifies a tracking delay in seconds between up and down states.

Step 7 

end

Example:

Router(config-track)# end

Returns to privileged EXEC mode.

Configuring a Tracked List and Threshold Percentage

Perform this task to configure a tracked list of objects, to specify that a percentage will be used as the threshold, and to specify a percentage for each object in the list. A tracked list contains one or more objects. Using the threshold percentage, the state of the list is determined by comparing the assigned percentage of each object to the list.

You may also configure a tracked list state to be measured using a Boolean calculation or threshold weight. See "Configuring a Tracked List and Boolean Expression" section and "Configuring a Tracked List and Threshold Weight" section.

Prerequisites

An object must exist before it can be added to a tracked list.

Restrictions

You cannot use the Boolean "not" operator in a weight or percentage threshold list.

SUMMARY STEPS

1. enable

2. configure terminal

3. track track-number list threshold percentage

4. object object-number

5. threshold percentage {up number [down number] | down number [up number]}

6. delay {up seconds [down seconds] | [up seconds] down seconds}

7. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track track-number list threshold percentage

Example:

Router(config-track)# track 100 list threshold percentage

Configures a tracked list object and enters tracking configuration mode. The keywords are as follows:

•threshold—Specifies that the state of the tracked list is based on a threshold.

•percentage—Specifies that the threshold is based on a percentage.

Step 4 

object object-number

Example:

Router(config-track)# object 3

Specifies the object to be tracked. The object-number argument has a valid range from 1 to 500. There is no default.

Step 5 

threshold percentage {up number [down number] | down number [up number]}

Example:

Router(config-track)# threshold percentage up 30

Specifies the threshold percentage. The keywords and arguments are as follows:

•up number—Valid range is from 1 to 100.

•down number—Range depends upon what you have selected for the up keyword. For example, if you specify 25 as up, a range from 26 to 100 is displayed for the down keyword.

Step 6 

delay {up seconds [down seconds] | [up seconds] down seconds}

Example:

Router(config-track)# delay up 3

(Optional) Specifies a tracking delay in seconds between up and down states.

Step 7 

end

Example:

Router(config-track)# end

Returns to privileged EXEC mode.

Configuring the Track List Defaults

Perform this task to configure a default delay value for a tracked list, a default object, and default threshold parameters for a tracked list.

SUMMARY STEPS

1. enable

2. configure terminal

3. track track-number

4. default {delay | object object-number | threshold percentage}

5. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

track track-number

Example:

Router(config)# track 3

Enters tracking configuration mode.

Step 4 

default {delay | object object-number | threshold percentage}

Example:

Router(config-track)# default delay

Specifies a default delay value for a tracked list, a default object, and default threshold parameters for a tracked list. The keywords and arguments are as follows:

•delay—Reverts to the default delay.

•object object-number—Specifies a default object for the track list. The valid range is from 1 to 500.

•threshold percentage—Specifies a default threshold percentage.

Step 5 

end

Example:

Router(config-track)# end

Returns to privileged EXEC mode.

Configuration Examples for Enhanced Object Tracking

•Example: Interface Line Protocol

•Example: Interface IP Routing

•Example: IP-Route Reachability

•Example: IP-Route Threshold Metric

•Example: IP SLAs IP Host Tracking

•Example: Boolean Expression for a Tracked List

•Example: Threshold Weight for a Tracked List

•Example: Threshold Percentage for a Tracked List

Example: Interface Line Protocol

The following example is very similar to the IP-routing example. Instead, the tracking process is configured to track the line-protocol state of GigabitEthernet interface 1/0/0. HSRP on GigabitEthernet interface 0/0/0 then registers with the tracking process to be informed of any changes to the line-protocol state of GigabitEthernet interface 1/0/0. If the line protocol on GigabitEthernet interface 1/0/0 goes down, the priority of the HSRP group is reduced by 10.

Router A Configuration 

Router(config)# track 100 interface GigabitEthernet1/0/0 line-protocol

!

Router(config)# interface GigabitEthernet0/0/0

Router(config-if)# ip address 10.1.0.21 255.255.0.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.0.1

Router(config-if)# standby 1 priority 110

Router(config-if)# standby 1 track 100 decrement 10

Router B Configuration 

Router(config)# track 100 interface GigabitEthernet1/0/0 line-protocol

!

Router(config)# interface GigabitEthernet0/0/0

Router(config-if)# ip address 10.1.0.22 255.255.0.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.0.1

Router(config-if)# standby 1 priority 105

Router(config-if)# standby 1 track 100 decrement 10

Example: Interface IP Routing

In the following example, the tracking process is configured to track the IP-routing capability of GigabitEthernet interface 1/0/0. HSRP on GigabitEthernet interface 0/0/0 then registers with the tracking process to be informed of any changes to the IP-routing state of GigabitEthernet interface 1/0/0. If the IP-routing state on GigabitEthernet interface 1/0/0 goes down, the priority of the HSRP group is reduced by 10.

If both serial interfaces are operational, Router A will be the HSRP active router because it has the higher priority. However, if IP on GigabitEthernet interface 1/0/0 in Router A fails, the HSRP group priority will be reduced and Router B will take over as the active router, thus maintaining a default virtual gateway service to hosts on the 10.1.0.0 subnet.

See Figure 1 for a sample topology.

Figure 1 Topology for IP-Routing Support

Router A Configuration 

Router(config)# track 100 interface GigabitEthernet1/0/0 ip routing

!

Router(config)# interface GigabitEthernet0/0/0

Router(config-if)# ip address 10.1.0.21 255.255.0.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.0.1

Router(config-if)# standby 1 priority 110

Router(config-if)# standby 1 track 100 decrement 10

Router B Configuration 

Router(config)# track 100 interface GigabitEthernet1/0/0 ip routing

!

Router(config)# interface GigabitEthernet0/0/0

Router(config-if)# ip address 10.1.0.22 255.255.0.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.0.1

Router(config-if)# standby 1 priority 105

Router(config-if)# standby 1 track 100 decrement 10

Example: IP-Route Reachability

In the following example, the tracking process is configured to track the reachability of IP route 10.2.2.0/24:

Router A Configuration 

Router(config)# track 100 ip route 10.2.2.0/24 reachability 

!

Router(config)# interface GigabitEthernet0/0/0 

Router(config-if)# ip address 10.1.1.21 255.255.255.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.1.1 

Router(config-if)# standby 1 priority 110 

Router(config-if)# standby 1 track 100 decrement 10

Router B Configuration 

Router(config)# track 100 ip route 10.2.2.0/24 reachability

!

Router(config)# interface GigabitEthernet0/0/0 

Router(config-if)# ip address 10.1.1.22 255.255.255.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.1.1 

Router(config-if)# standby 1 priority 105

Router(config-if)# standby 1 track 100 decrement 10

Example: IP-Route Threshold Metric

In the following example, the tracking process is configured to track the threshold metric of IP route 10.2.2.0/24:

Router A Configuration 

Router(config)# track 100 ip route 10.2.2.0/24 metric threshold

! 

Router(config)# interface GigabitEthernet0/0/0 

Router(config-if)# ip address 10.1.1.21 255.255.255.0

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.1.1 

Router(config-if)# standby 1 priority 110 

Router(config-if)# standby 1 track 100 decrement 10

Router B Configuration 

Router(config)# track 100 ip route 10.2.2.0/24 metric threshold

! 

Router(config)# interface GigabitEthernet0/0/0 

Router(config-if)# ip address 10.1.1.22 255.255.255.0 

Router(config-if)# standby 1 preempt

Router(config-if)# standby 1 ip 10.1.1.1 

Router(config-if)# standby 1 priority 105 

Router(config-if)# standby 1 track 100 decrement 10

Example: IP SLAs IP Host Tracking

The following example shows how to configure IP host tracking for IP SLAs operation 1 in Cisco IOS XE releases prior to Cisco IOS XE Release 2.4: 

Router(config)# ip sla 1

Router(config-ip-sla)# icmp-echo 10.51.12.4

Router(config-ip-sla-echo)# timeout 1000

Router(config-ip-sla-echo)# frequency 3

Router(config-ip-sla-echo)# threshold 2

Router(config-ip-sla-echo)# request-data-size 1400

Router(config-ip-sla-echo)# exit

Router(config)# ip sla schedule 1 start-time now life forever

Router(config-ip-sla)# exit

Router(config)# track 2 rtr 1 state

Router(config)# track 3 rtr 1 reachability

Router(config-track)# exit

Router(config)# interface GigabitEthernet0/1/0

Router(config-if)# ip address 10.21.0.4 255.255.0.0

Router(config-if)# no shutdown

Router(config-if)# standby 3 ip 10.21.0.10d

Router(config-if)# standby 3 priority 120

Router(config-if)# standby 3 preempt

Router(config-if)# standby 3 track 2 decrement 10

Router(config-if)# standby 3 track 3 decrement 10

The following example shows how to configure IP host tracking for IP SLAs operation 1 in Cisco IOS XE Release 2.4 and later releases: 

Router(config)# ip sla 1

Router(config-ip-sla)# icmp-echo 10.51.12.4

Router(config-ip-sla-echo)# timeout 1000

Router(config-ip-sla-echo)# frequency 3

Router(config-ip-sla-echo)# threshold 2

Router(config-ip-sla-echo)# request-data-size 1400

Router(config-ip-sla-echo)# exit

Router(config)# ip sla schedule 1 start-time now life forever

Router(config-ip-sla)# exit

Router(config)# track 2 ip sla 1 state

Router(config)# track 3 ip sla 1 reachability

Router(config-track)# exit

Router(config)# interface gigabitethernet0/1/1

Router(config-if)# ip address 10.21.0.4 255.255.0.0

Router(config-if)# no shutdown

Router(config-if)# standby 3 ip 10.21.0.10d

Router(config-if)# standby 3 priority 120

Router(config-if)# standby 3 preempt

Router(config-if)# standby 3 track 2 decrement 10

Router(config-if)# standby 3 track 3 decrement 10

Example: Boolean Expression for a Tracked List

In the following example, a track list object is configured to track two GigabitEthernet interfaces when both interfaces are up and when either interface is down: 

Router(config)# track 1 interface GigabitEthernet2/0/0 line-protocol

Router(config)# track 2 interface GigabitEthernet2/1/0 line-protocol

Router(config-track)# exit

Router(config)# track 100 list boolean and

Router(config-track)# object 1

Router(config-track)# object 2

In the following example, a track list object is configured to track two GigabitEthernet interfaces when either interface is up and when both interfaces are down: 

Router(config)# track 1 interface GigabitEthernet2/0/0 line-protocol

Router(config)# track 2 interface GigabitEthernet2/1/0 line-protocol

Router(config-track)# exit

Router(config)# track 101 list boolean or

Router(config-track)# object 1

Router(config-track)# object 2

The following configuration example shows that tracked list 4 has two objects and one object state is negated (if the list is up, the list detects that object 2 is down): 

Router(config)# track 4 list boolean and

Router(config-track)# object 1

Router(config-track)# object 2 not

Example: Threshold Weight for a Tracked List

In the following example, three GigabitEtherent interfaces in tracked list 100 are configured with a threshold weight of 20 each. The down threshold is configured to 0 and the up threshold is configured to 40: 

Router(config)# track 1 interface GigabitEthernet2/0/0 line-protocol

Router(config)# track 2 interface GigabitEthernet2/1/0 line-protocol

Router(config)# track 3 interface GigabitEthernet2/2/0 line-protocol

Router(config-track)# exit

Router(config)# track 100 list threshold weight

Router(config-track)# object 1 weight 20

Router(config-track)# object 2 weight 20

Router(config-track)# object 3 weight 20

Router(config-track)# threshold weight down 0 up 40

The above example means that the track-list object goes down only when all three serial interfaces go down, and only comes up again when at least two interfaces are up (since 20+20 >= 40). The advantage of this configuration is that it prevents the track-list object from coming up if two interfaces are down and the third interface is flapping.

The following configuration example shows that if object 1 and object 2 are down, then track list 4 is up, because object 3 satisfies the up threshold value of up 30. But, if object 3 is down, both objects 1 and 2 need to be up in order to satisfy the threshold weight. 

Router(config)# track 4 list threshold weight

Router(config-track)# object 1 weight 15

Router(config-track)# object 2 weight 20

Router(config-track)# object 3 weight 30

Router(config-track)# threshold weight up 30 down 10

This configuration may be useful to you if you have two small bandwidth connections (represented by object 1 and 2) and one large bandwidth connection (represented by object 3). Also the down 10 value means that once the tracked object is up, it will not go down until the threshold value is lower or equal to 10, which in this example means that all connections are down.

Example: Threshold Percentage for a Tracked List

In the following example, four GigabitEthernet interfaces in track list 100 are configured for an up threshold percentage of 75. The track list is up when 75 percent of the interfaces are up and down when fewer than 75 percent of the interfaces are up. 

Router(config)# track 1 interface GigabitEthernet2/0/0 line-protocol

Router(config)# track 2 interface GigabitEthernet2/1/0 line-protocol

Router(config)# track 3 interface GigabitEthernet2/2/0 line-protocol

Router(config)# track 4 interface GigabitEthernet2/3/0 line-protocol

Router(config-track)# exit

Router(config)# track 100 list threshold percentage

Router(config-track)# object 1

Router(config-track)# object 2

Router(config-track)# object 3

Router(config-track)# object 4

Router(config-track)# threshold percentage up 75

Additional References

Related Documents

Related Topic
Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

Embedded Event Manager

Embedded Event Manager Overview

HSRP concepts and configuration tasks

Configuring HSRP

GLBP concepts and configuration tasks

Configuring GLBP

IP SLAs commands

Cisco IOS IP SLAs Command Reference

VRRP concepts and configuration tasks

Configuring VRRP

GLBP, HSRP, and VRRP commands

Cisco IOS IP Application Services Command Reference.


Standards

Standards
Title

No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.

—


MIBs

MIBs
MIBs Link

No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature.

To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs


RFCs

RFCs
Title

No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.

—


Technical Assistance

Description
Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html


Feature Information for Enhanced Object Tracking

Table 3 lists the features in this module and provides links to specific configuration information.

Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Note Table 3 lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Table 3 Feature Information for Enhanced Object Tracking 

Feature Name
Releases
Feature Configuration Information

Enhanced Tracking Support

Cisco IOS XE
Release 2.1

The Enhanced Tracking Support feature separates the tracking mechanism from HSRP and creates a separate standalone tracking process that can be used by other Cisco IOS XE processes as well as HSRP. This feature allows tracking of other objects in addition to the interface line-protocol state.

The following sections provide information about this feature:

•IP-Routing State of an Interface

•Scaled Route Metrics

•Tracking the Line-Protocol State of an Interface

•Tracking the IP-Routing State of an Interface

•Tracking IP-Route Reachability

•Tracking the Threshold of IP-Route Metrics

•Example: Interface Line Protocol

•Example: Interface IP Routing

•Example: IP-Route Reachability

•Example: IP-Route Threshold Metric

The following commands were introduced or modified by this feature: debug track, delay tracking, ip vrf, show track, standby track, threshold metric, track interface, track ip route, track timer.

FHRP—Enhanced Object Tracking of IP SLAs Operations

Cisco IOS XE Release 2.1

This feature enables First Hop Redundancy Protocols (FHRPs) and other Enhanced Object Tracking (EOT) clients to track the output from IP SLAs objects and use the provided information to trigger an action.

The following section provides information about this feature:

•Tracking IP SLAs Operations

•Tracking the State of an IP SLAs Operation

•Example: IP SLAs IP Host Tracking

•Example: Boolean Expression for a Tracked List

The following command was introduced by this feature: track rtr.

FHRP—Object Tracking List

Cisco IOS XE Release 2.1

This feature enhances the tracking capabilities to enable the configuration of a combination of tracked objects in a list, and a flexible method of combining objects using Boolean logic.

The following sections provide information about this feature:

•Configuring a Tracked List and Boolean Expression

•Configuring a Tracked List and Threshold Weight

•Configuring a Tracked List and Threshold Percentage

•Configuring the Track List Defaults

The following commands were introduced or modified by this feature: show track, threshold percentage, threshold weight, track list, track resolution.

FHRP—EOT Deprecation of rtr Keyword

Cisco IOS XE Release 2.4

This feature replaces the track rtr command with the track ip sla command.

The following sections provide information about this feature:

•Tracking the State of an IP SLAs Operation

•Example: IP SLAs IP Host Tracking

The following command was introduced by this feature: track ip sla.

FHRP—Enhanced Object Tracking Integration with Embedded Event Manager

Cisco IOS XE Release 2.1

EOT is now integrated with EEM to allow EEM to report on a status change of a tracked object and to allow EOT to track EEM objects.

The following section provides information about this feature:

•Enhanced Object Tracking and Embedded Event Manager

The following commands were introduced or modified by this feature: action track read, action track set, default-state, event resource, event rf, event track, show track, track stub.


Glossary

DHCP—Dynamic Host Configuration Protocol. DHCP is a protocol that delivers IP addresses and configuration information to network clients.

GLBP—Gateway Load Balancing Protocol. Provides automatic router backup for IP hosts that are configured with a single default gateway on an IEEE 802.3 LAN. Multiple first-hop routers on the LAN combine to offer a single virtual first-hop IP router while sharing the IP packet forwarding load. Other routers on the LAN may act as redundant (GLBP) routers that will become active if any of the existing forwarding routers fail.

HSRP—Hot Standby Router Protocol. Provides high network availability and transparent network topology changes. HSRP creates a Hot Standby router group with a lead router that services all packets sent to the Hot Standby address. The lead router is monitored by other routers in the group, and if it fails, one of these standby routers inherits the lead position and the Hot Standby group address.

IPCP—IP Control Protocol. The protocol used to establish and configure IP over PPP.

LCP—Link Control Protocol. The protocol used to establish, configure, and test data-link connections for use by PPP.

PPP—Point-to-Point Protocol. Provides router-to-router and host-to-network connections over synchronous and asynchronous circuits. PPP is most commonly used for dial-up Internet access. Its features include address notification, authentication via CHAP or PAP, support for multiple protocols, and link monitoring.

VRF—VPN routing and forwarding instance. A VRF consists of an IP routing table, a derived forwarding table, a set of interfaces that use the forwarding table, and a set of rules and routing protocols that determine what goes into the forwarding table. In general, a VRF includes the routing information that defines a customer VPN site that is attached to a provider edge router.

VRRP—Virtual Router Redundancy Protocol. Eliminates the single point of failure inherent in the static default routed environment. VRRP specifies an election protocol that dynamically assigns responsibility for a virtual router to one of the VRRP routers on a LAN. The VRRP router that controls the IP addresses associated with a virtual router is called the master, and forwards packets sent to these IP addresses. The election process provides dynamic failover in the forwarding responsibility should the master become unavailable. Any of the virtual router IP addresses on a LAN can then be used as the default first-hop router by end hosts.

Cisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks. Third party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1005R)

Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

© 2005-2011 Cisco Systems, Inc. All rights reserved.