SSH Login Without Password Using ssh-keygen & ssh-copy-id Chúng ta có thể login từ xa vào máy chủ Linux mà không cần password với 3 bước đơn giản sử dụng ssh-keygen, ssh-copy-id. + ssh-keygen dùng để tạo public và private keys + ssh-copy-id dùng để copy public key trên local-host vào file authorized_keys trên remote-host. + ssh-copy-id cũng chỉ định permission thích hợp đối với /.ssh, và ~/.ssh/authorized_keys trên remote-host. Step 1: Create public and private keys using ssh-key-gen on local-host jsmith@local-host$ [Note: You are on local-host here] jsmith@local-host$ ssh-keygen Generating public/private rsa key pair. Enter file in which to save the key (/home/jsmith/.ssh/id_rsa):[Enter key] Enter passphrase (empty for no passphrase): [Press enter key] Enter same passphrase again: [Pess enter key] Your identification has been saved in /home/jsmith/.ssh/id_rsa. Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub. The key fingerprint is: 33:b3:fe:af:95:95:18:11:31:d5:de:96:2f:f2:35:f9 jsmith@local-host Step 2: Copy the public key to remote-host using ssh-copy-id
jsmith@remote-host's password: Now try logging into the machine, with "ssh 'remote-host'", and check in:
.ssh/authorized_keys
to make sure we haven't added extra keys that you weren't expecting.
Note: ssh-copy-id appends the keys to the remote-host’s .ssh/authorized_key.
Step 3: Login to remote-host without entering the password
jsmith@local-host$ ssh remote-host Last login: Sun Nov 16 17:22:33 2008 from 192.168.1.2 [Note: SSH did not ask for password.]
jsmith@remote-host$ [Note: You are on remote-host here] |