ssh -i private-key.pem ubuntu@ip.address #for the root
ssh -i private-key.pem elspeth@ip.address #for the user

debug2: we sent a publickey packet, wait for reply
debug1: Authentications that can continue: publickey
debug2: we did not send a packet, disable method
debug1: No more authentication methods to try.
Permission denied (publickey).

drwx------   7 user  staff    238 Nov 24 11:39 ~/.ssh

-rw-------  1 user  staff   668 Nov 24 11:36 id_dsa
-rw-r--r--  1 user  staff   621 Nov 24 11:36 id_dsa.pub
-rw-------  1 user  staff  1679 Nov 24 11:39 id_rsa
-rw-r--r--  1 user  staff   413 Nov 24 11:39 id_rsa.pub
-rw-r--r--  1 user  staff   395 Nov 24 11:37 known_hosts

drwx------ 2 elspeth elspeth 4096 Nov 24 19:42 /home/elspeth/.ssh

-rw------- 1 elspeth elspeth 1034 Nov 24 19:42 /home/elspeth/.ssh/authorized_keys