How can I start a server which just shutdown

I am a junior for web design&server. ten minutes ago, I want to fix some problem with mysql on CentOS server, but I use a wrong command and I'm not discover:

shutdown -h now

now, this server is already shutdown... I usually use ssh to connect, it doesn't work now. I just have a few informations with this server...

it's user centOS 6.6 and it might be amazon-web-services, and i have ip, port, root password

is there any way that I can use to restart this server? with this informations...

Thanks...