Notes: Please config static ip when launch instance. Because change dynamic public ip to static ip, it will
cause ssh connect refused.
The way for config static ip when launch instance is as the followings:
new alloc static ip
new alloc network interface
associate ip and interface
associate network interface with instance when launch instance
AWS Intro - Static IP with ssh
原文：http://www.cnblogs.com/avcs/p/6904585.html