- Index
- Preface
- Overview
- Using the Command-Line Interface
- Assigning the Switch IP Address and Default Gateway
- Configuring Cisco IOS Configuration Engine
- Clustering Switches
- Administering the Switch
- Configuring SDM Templates
- Configuring Switch-Based Authentication
- Configuring IEEE 802.1x Port-Based Authentication
- Configuring Web-Based Authentication
- Configuring Interface Characteristics
- Configuring VLANs
- Configuring VTP
- Configuring Voice VLAN
- Configuring Private VLANs
- Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling
- Configuring STP
- Configuring MSTP
- Configuring Optional Spanning-Tree Features
- Configuring Flex Links and the MAC Address-Table Move Update Feature
- Configuring DHCP Features and IP Source Guard
- Configuring Dynamic ARP Inspection
- Configuring IGMP Snooping and MVR
- Configuring Port-Based Traffic Control
- Configuring CDP
- Configuring LLDP, LLDP-MED, and Wired Location Service
- Configuring UDLD
- Configuring SPAN and RSPAN
- Configuring RMON
- Configuring System Message Logging
- Configuring SNMP
- Configuring Embedded Event Manager
- Configuring Network Security with ACLs
- Configuring QoS
- Configuring EtherChannels and Link-State Tracking
- Configuring TelePresence E911 IP Phone Support
- Configuring IP Unicast Routing
- Configuring IPv6 Routing
- Configuring IPv6 ACLs
- Configuring IPv6 MLD Snooping
- Configuring HSRP and VRRP
- Configuring Cisco IOS IP SLAs Operations
- Configuring Enhanced Object Tracking
- Configuring Cache Services By Using WCCP
- Configuring IP Multicast Routing
- Configuring MSDP
- Configuring Fallback Bridging
- Troubleshooting
- Configuring Online Diagnostics
- Working with the Cisco IOS File System, Configuration Files, and Software Images
- Unsupported Commands in Cisco IOS Release 12.2(58)SE
- Understanding Enhanced Object Tracking
- Configuring Enhanced Object Tracking Features
Configuring Enhanced Object Tracking
This chapter describes how to configure enhanced object tracking on the Catalyst 3560 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.
For more information about enhanced object tracking and the commands used to configure it:
http://www.cisco.com/en/US/docs/ios/ipapp/configuration/guide/ipapp_eot.html
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.
Configuring Enhanced Object Tracking Features
These sections describe configuring enhanced object tracking:
- Default Configuration
- Tracking Interface Line-Protocol or IP Routing State
- Configuring a Tracked List
- Configuring HSRP Object Tracking
- Configuring Other Tracking Characteristics
- Configuring IP SLAs Object Tracking
- Configuring Static Routing Support
Default Configuration
Tracking Interface Line-Protocol or IP Routing State
You can track either the interface line protocol state or the interface IP routing state. When you track the IP routing state, these three conditions are required for the object to be up:
- IP routing must be enabled and active on the interface.
- The interface line-protocol state must be up.
- The interface IP address must be known.
If all three of these conditions are not met, the IP routing state is down.
Beginning in privileged EXEC mode, follow these steps to track the line-protocol state or IP routing state of an interface:
This example configures the tracking of an interface line-protocol state and verifies the configuration:
Configuring a Tracked List
You can configure a tracked list of objects with a Boolean expression, a weight threshold, or a percentage threshold. A tracked list contains one or more objects. An object must exist before it can be added to the tracked list.
- You configure a Boolean expression to specify calculation by using either “AND” or “OR” operators.
- When you measure the tracked list state by a weight threshold, you assign a weight number to each object in the tracked list. The state of the tracked list is determined by whether or not the threshold was met. The state of each object is determined by comparing the total weight of all objects against a threshold weight for each object.
- When you measure the tracked list by a percentage threshold, you assign a percentage threshold to all objects in the tracked list. The state of each object is determined by comparing the assigned percentages of each object to the list.
Configuring a Tracked List with a Boolean Expression
Configuring a tracked list with a Boolean expression enables calculation 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.
Beginning in privileged EXEC mode, follow these steps to configure a tracked list of objects with a Boolean expression:
Use the no track track-number global configuration command to delete the tracked list.
This example configures track list 4 with a Boolean AND expression that contains two objects with one object state negated. If the list is up, the list detects that object 2 is down:
Configuring a Tracked List with a Weight Threshold
To track by weight threshold, configure a tracked list of objects, specify that weight is used as the threshold, and configure a weight for each of its objects. 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 cannot use the Boolean “NOT” operator in a weight threshold list.
Beginning in privileged EXEC mode, follow these steps to configure a tracked list of objects by using a weight threshold and to configure a weight for each object:
Use the no track track-number global configuration command to delete the tracked list.
The example configures track list 4 to track by weight threshold. 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 must be up in order to satisfy the threshold weight.
This configuration can be useful if object 1 and object 2 represent two small bandwidth connections and object 3 represents one large bandwidth connection. The configured down 10 value means that once the tracked object is up, it will not go down until the threshold value is equal to or lower than 10, which in this example means that all connections are down.
Configuring a Tracked List with a Percentage Threshold
To track by percentage threshold, configure a tracked list of objects, specify that a percentage will be used as the threshold, and specify a percentage for all objects in the list. The state of the list is determined by comparing the assigned percentage of each object to the list.
You cannot use the Boolean “NOT” operator in a percentage threshold list.
Beginning in privileged EXEC mode, follow these steps to configure a tracked list of objects by using a percentage threshold:
Use the no track track-number global configuration command to delete the tracked list.
This example configures tracked list 4 with three objects and a specified percentages to measure the state of the list:
Configuring HSRP Object Tracking
Beginning in privileged EXEC mode, follow these steps to configure a standby HSRP group to track an object and change the HSRP priority based on the object state:
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track object-number { interface interface-id { line-protocol | i p routing} | ip route ip-address/prefix-length { metric threshold | reachability } | list { boolean { and | or }} | { threshold { weight | percentage }}} |
(Optional) Create a tracking list to track the configured state and enter tracking configuration mode.
The default up threshold is 254 and the default down threshold is 255.
– For boolean, see the “Configuring a Tracked List with a Boolean Expression” section – For threshold weight, see the “Configuring a Tracked List with a Weight Threshold” section – For threshold percentage, see the “Configuring a Tracked List with a Percentage Threshold” section |
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Create (or enable) the HSRP group by using its number and virtual IP address.
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standby [ group-number ] track object-number [ decrement [ priority-decrement ]] |
Configure HSRP to track an object and change the hot standby priority based on the state of the object.
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Configuring Other Tracking Characteristics
You can also use the enhanced object tracking for tracking other characteristics.
- You can track the reachability of an IP route by using the track ip route reachability global configuration command.
- You can use the track ip route metric threshold global configuration command to determine if a route is above or below threshold.
- You can use the track resolution global configuration command to change the metric resolution default values for routing protocols.
- You can use the track timer tracking configuration command to configure the tracking process to periodically poll tracked objects.
Use the show track privileged EXEC command to verify enhanced object tracking configuration.
For more information about enhanced object tracking and the commands used to configure it:
http://www.cisco.com/en/US/docs/ios/ipapp/configuration/guide/ipapp_eot.html
Configuring IP SLAs Object Tracking
Cisco IOS IP Service Level Agreements (IP SLAs) is a network performance measurement and diagnostics tool that uses active monitoring by generating traffic to measure network performance. Cisco IP SLAs operations collects real-time metrics that you can use for network troubleshooting, design, and analysis.
For more information about Cisco IP SLAs on the switch, see Chapter42, “Configuring Cisco IOS IP SLAs Operations” For IP SLAs command information see the Cisco IOS IP SLAs Command Reference, Release 12.4T :
http://www.cisco.com/en/US/docs/ios/ipsla/command/reference/sla_book.html
Object tracking of IP SLAs operations allows clients to track the output from IP SLAs objects and use this information to trigger an action. Every IP SLAs operation maintains an SNMP operation return-code value, such as OK or OverThreshold, that can be interpreted by the tracking process. You can track two aspects of IP SLAs operation: state and reachability. For state, if the return code is OK, the track state is up; if the return code is not OK, the track state is down. For reachability, if the return code is OK or OverThreshold, reachability is up; if not OK, reachability is down.
Beginning in privileged EXEC mode, follow these steps to track the state of an IP SLAs operation or the reachability of an IP SLAs IP host:
This example shows how to configure and display IP SLAs state tracking:
This example output shows whether a route is reachable:
Configuring Static Routing Support
Switches that are running the IP services image with Cisco IOS release 12.2(46)SE or later support enhanced object tracking static routing. Static routing support using enhanced object tracking provides the ability for the switch to use ICMP pings to identify when a preconfigured static route or a DHCP route goes down. When tracking is enabled, the system tracks the state of the route and informs the client when that state changes. Static route object tracking uses Cisco IP SLAs to generate ICMP pings to monitor the state of the connection to the primary gateway.
- For more information about Cisco IP SLAs support on the switch, see Chapter42, “Configuring Cisco IOS IP SLAs Operations”
- For more information about static route object tracking:
http://www.cisco.com/en/US/docs/ios/12_3/12_3x/12_3xe/feature/guide/dbackupx.html
You use this process to configure static route object tracking:
Step 1 Configure a primary interface for static routing or for DHCP.
Step 2 Configure an IP SLAs agent to ping an IP address using a primary interface and a track object to monitor the state of the agent.
Step 3 Configure a default static default route using a secondary interface. This route is used only if the primary route is removed.
Configuring a Primary Interface
Beginning in privileged EXEC mode, follow these steps to configure a primary interface for static routing:
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Select a primary or secondary interface and enter interface configuration mode. |
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Beginning in privileged EXEC mode, follow these steps to configure a primary interface for DHCP:
Configuring a Cisco IP SLAs Monitoring Agent and Track Object
Beginning in privileged EXEC mode, follow these steps to configure network monitoring with Cisco IP SLAs:
Configuring a Routing Policy and Default Route
Beginning in privileged EXEC mode, follow these steps to configure a routing policy for backup static routing by using object tracking. For more details about the commands in the procedure:
http://www.cisco.com/en/US/docs/ios/12_3/12_3x/12_3xe/feature/guide/dbackupx.html
For configuration examples:
http://www.cisco.com/en/US/docs/ios/12_3/12_3x/12_3xe/feature/guide/dbackupx.html
Monitoring Enhanced Object Tracking
Use the privileged EXEC or User EXEC commands in Table 43-1 to display enhanced object tracking information.
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Display information about the all tracking lists or the specified list. |
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