Permissions 0664 for '/home/ec2-user/.ssh/id_rsa' are too open. code example
Example 1: Permissions 0664 for '/home/kapua/keys/dev11' are too open.
chmod 600 ~/.ssh/id_rsa
Example 2: it is required that your private key files are not accessible by others
$ sudo chmod 600 /path/to/my/key.pem