The procedure for setting ssh key authentication is the same if you use it for sshfs or something else.
On the client side, you create a key. In this case, we make the DSA key
ssh-keygen -t dsa
id_dsa id_dsa.pub .ssh. , authorized_keys ( authorized_keys2, DSA, ) .ssh , .
Linux, , ssh-copy-id.
ssh-copy-id user@server:
id_dsa 600 , . authorized_keys , , , root.