Elastic IPs in Amazon EC2

Question

When I use Elastic IPs in I can't use SSH. When I try to login, following message is show

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.

Answer 1

Edit your .ssh/known_hosts file and delete the line corresponding to your AMI.

The problem is that the first time you connected, ssh saved the remote key of that machine you connected to, and when you enabled Elastic IPs, that remote key changed.

http://developer.amazonwebservices.com/connect/thread.jspa;?messageID=104781&#104781

Answer 2

Alternatively, use ssh-keygen -R <hostname|IP address> to remove the entry from the known_hosts file.