client

cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 700 ~/.ssh
chmod 600 ~/.ssh/authorized_keys

server

chmod 700 ~/.ssh
cat ~/id_dsa.pub >> ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys

server config

/etc/ssh/sshd_config

PubkeyAuthentication yes
//公開鍵認証を許可
PasswordAuthentication no
//パスワードでのログインを禁止
PermitRootLogin no
//rootでのログインを禁止

restart

sudo /etc/rc.d/init.d/sshd restart