scp -vvv –P 4321 ~/.ssh/id_rsa.pub  javier@my_IP:

debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey
debug1: Trying private key: /Users/Sanchezj/.ssh/id_dsa
debug3: no such identity: /Users/Sanchezj/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /Users/Sanchezj/.ssh/id_ecdsa
debug3: no such identity: /Users/Sanchezj/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /Users/Sanchezj/.ssh/id_ed25519
debug3: no such identity: /Users/Sanchezj/.ssh/id_ed25519: No such file or directory
debug2: we did not send a packet, disable method
debug1: No more authentication methods to try.
javier@192.168.1.3: Permission denied (publickey).
lost connection

ssh-copy-id -p 4321 my_IP