link s1 s2 down
This will bring the link between switch1 (s1) and switch2 (s2) down
link s1 s2 up
This will bring the link between switch1 (s1) and switch2 (s2) up
link s1 h1 down
This will bring the link between switch1 (s1) and host1 (h1) down
link s1 s2 down
This will bring the link between switch1 (s1) and switch2 (s2) down
link s1 s2 up
This will bring the link between switch1 (s1) and switch2 (s2) up
link s1 h1 down
This will bring the link between switch1 (s1) and host1 (h1) down