permission denied (public key issue)

I have created an instance of amazon unix/linux on aws ec2, when i tried to access my instance from my u开发者_高级运维buntu console I am getting an error "ssh -i mpigeon.pem ec2-50-17-134-152.compute-1.amazonaws.com Permission denied (publickey)."

What is the issue how do I resolve it

You need to mention the user name while login into instance.

ssh -i mpigeon.pem root@ec2-50-17-134-152.compute-1.amazonaws.com

If you are using ubuntu instance, default user in ubuntu. Replace root user with ubuntu user else for centos and fedora, default user is root only.