How to track an object in the down state

Usually you're tracking an object and making some actions when the object is up:

track 1 interface Ethernet0/0 line-protocol
!
ip route 100.0.0.0 255.255.255.0 Null0 track 1

The static route is installed when interface Ethernet0/0 is up.


If you want to achieve the opposite:

track 1 interface Ethernet0/0 line-protocol
!
track 3 list boolean and
 object 1 not
!
ip route 100.0.0.0 255.255.255.0 Null0 track 3

The static route is installed when interface Ethernet0/0 is down.