Connect over ssh using a .pem file

Use the -i option:

ssh -i mykey.pem [email protected]

As noted in this answer, this file needs to have correct permissions set. The ssh man page says:

ssh will simply ignore a private key file if it is accessible by others.

You can change the permissions with this command:

chmod go= mykey.pem

That is, set permissions for group and others equal to the empty list of permissions.

chmod 400 mykey.pem

ssh -i mykey.pem [email protected]

Will connect you over ssh using a .pem file to any server.

For AWS if the user is ubuntu use the following to connect to remote server.

chmod 400 mykey.pem

ssh -i mykey.pem ubuntu@your-ip