Run an EEM applet on a tracking event

In this lab, one Cisco router tracks reachability to the other.

Check that the tracked target is reachable before configuring the applets.

Register one applet to add a test route when tracking goes down and another to remove it when tracking recovers.

Shut the far interface and check that the first applet ran and installed the route.

Bring the interface back up and verify that the recovery applet removed the route.

Remove the down applet and repeat the failure to confirm that the route is no longer added.