1. Set up a switch with 2 or 3 hosts in the same VLAN.
2. Ping one host from the other.
3. Take an ethernet cable and plug both ends of it into the switch.
4. Try and ping now. Hahahaha. You can't, can you?
5. Console in to the switch and see if it can ping the hosts connected to it.
6. Are any lights on the switch flashing that shouldn't be flashing? Are there any lights flashing in a way that seems unusual?
7. Unplug one end of the ethernet cable.
8. Things should be working fine now, verify with ping tests.
9. Plug as many switches together as you like, adding a few hosts to each switch. Do ping tests to make sure everybody's happy.
10. Now plug that other end of the ethernet cable back into the switch.
11. Everything went down, am I right?
12. What is going on, here?
:zomgwtfbbq: