Permissions 0664 for 'fxpem' are too open. It is required that your private key files are NOT accessible by others. This private key will be ignored. Load key "frontend-dev.pem": bad permissions code example
Example 1: Permissions 0664 for '/home/kapua/keys/dev11' are too open.
chmod 600 ~/.ssh/id_rsaExample 2: it is required that your private key files are not accessible by others
$ sudo chmod 600 /path/to/my/key.pem