使用下例中ssky-keygen和ssh-copy-id，僅需通過3個步驟的簡單設置，你無需輸入密碼就能登錄遠程Linux主機。

ssh-keygen 創建公鑰和密鑰。 ssh-copy-id 把本地主機的公鑰復制到遠程主機的authorized_keys文件上。ssh-copy-id也會給遠程主機的用戶主目錄（home）和~/.ssh, 和~/.ssh/authorized_keys設置合適的權限 。

步驟1: 用 ssh-key-gen在本地主機上創建公鑰和密鑰

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:f9jsmith@local-host

步驟2:用 ssh-copy-id 把公鑰復制到遠程主機上

jsmith@local-host$ssh-copy-id -i ~/.ssh/id_rsa.pub remote-host
jsmith@remote-host‘s password: 
Now try logging into the machine, with ―ssh 爠攀洀漀琀攀-host‘‖, and check in: 
.ssh/authorized_keys to make sure we haven‘t added extra keys that you weren‘texpecting. 
[注:ssh-copy-id 把密鑰追加到遠程主機的 .ssh/authorized_key 上.]

步驟3:直接登錄遠程主機

jsmith@local-host$ssh remote-host 
Last login: Sun Nov 16 17:22:33 2008 from 192.168.1.2 
[注: SSH 不會詢問密碼.]
jsmith@remote-host$ [注: 你現在已經登錄到了遠程主機上]

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