I shutdown my printer and Octoprint (from the website) a while back because I was going away and did not want to leave them going while no one was home. I just tried to restart my Octoprint and can't reconnect on the Website. It says that the site is "unreachable"...
Nevermind, the Octoprint server was just not working...its working fine now!
When you choose "shut down", it does a full shutdown of the raspberry pi. To get it back online, you need to power cycle it.