Is it possible to track the interface running hsrp?
ip address 10.1.1.21 255.255.255.248
standby 5 ip 10.1.1.22
standby 5 priority 200
standby 5 preempt
standby 5 track Serial1/0 20
standby 5 track GigabitEthernet0/0 20
I do not believe that it is possible to track the interface itself that HSRP is running on. And if it was possible I am not sure why you would want to do this.
The purpose of tracking an interface is so that you can decrease the priority of an interface running HSRP if some other interface goes down. If the interface running HSRP goes down you do not want to decrease its priority you want the other standby interface to take completely over.