生成秘钥

ssh-keygen -t [rsa|dsa]

将会生成密钥文件和私钥文件 id_rsa,id_rsa.pub或id_dsa,id_dsa.pub

将 .pub 文件复制到B机器的 .ssh 目录， 并 cat id_dsa.pub >> ~/.ssh/authorized_keys

设置authorized_keys权限
chmod 600 authorized_keys 
设置.ssh目录权限
chmod 700 -R .ssh

拷贝秘钥

ssh-copy-id [-i [identity_file]] [user@]machine

ssh-copy-id [-h|-?|-f|-n] [-i [identity_file]] [-p port] [[-o <ssh -o options>] ...] [user@]hostname

例如：

ssh-copy-id -i /root/.ssh/id_rsa.pub -p 2188 root@192.168.3.23 

登陆测试

ssh   root@192.168.3.23