HSRP Tracking

sharma16031981 · ‎06-08-2010

Hello All,

I have read HSRP and have some knowledge of interface tracking but not able to understand the concept of tracking . Could you please explain about the scenario where this feature would be required and also what will be the effect if interface tracking not used.

In normal scenario everything looks working fine without tracking.

Thanks,

Hemant Sharma

Federico Coto Fajardo · ‎06-08-2010

Hi Hemant,

Interface tracking in HSRP allows the priority on particular interfaces to go down an specific value, so that you can manage which device will become active if this happens.

Here's an example:

http://www.cisco.com/en/US/docs/internetworking/case/studies/cs009.html#wp3475

Federico.

sharma16031981 · ‎06-12-2010

Hi Federico,

Still I am not able to understand the concept is applicable in both cases where dynamic routing or static routing is in use.

Thanks

Hemant Sharma

Richard Burts · ‎06-12-2010

Hemant

There are several ways to do tracking. Your original post seems to be asking about tracking interfaces in the operation of HSRP. This post asks about trackig in terms of static routing or dynamic routing. These are quite different aspects of tracking.

In the context of HSRP it can be very helpful to track the operational status of an interface. For example Interface FastEthernet0/0 may be an interface configured with HSRP and FastEthernet0/1 may be the outbound interface to other subnets. It is possible that the router may have lost connectivity through interface FastEthernet0/1 (it can not ping the next hop out that interface) but the interface will still show as up/up. Configuring tracking will give you the ability to recognize when connectivity is lost and to adjust the priority of FastEthernet0/0 in HSRP.

A different situation may involve static routing. You may have a static route configured with the next hop being out interface FastEthernet0/1. There could be a problem in the network and the next hop address may no longer be reachable. But the interface will show as up and the static route will remain in the routing table. If you configure tracking on the interface it may allow you to detect when the next hop is no longer reachable and to withdraw that static route from the routing table.

HTH

Rick

HTH

Rick

Chetan Kumar Ress · ‎06-08-2010

Hi

HSRP Tracking is used track the WAN interface. For Example :

WAN WAN

| |

Router A ------- Router B

| |

LAN LAN

Here you can see , you had configured HSRP in LAN for Redundancy. If router A is Active & Router B is Standby the all trafic will hit router A.

And if router A WAN Link goes down then what happen ??

All trafic will stuck in router A. So If you configured Tracking then it will track the router A WAN interface & When ever it goes down then it will shift thr traffic to router B.

Regards

Chetan Kumar