Public key authentication allows you to login to a remote host via the SSH protocol without a password and is more secure than password-based authentication. Try creating a passwordless connection from linuxconfig.local to using public-key authentication.

1. Create key

Press ENTER at every prompt.

linuxconfig.local$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/user/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/user/.ssh/id_rsa.
Your public key has been saved in /home/user/.ssh/
The key fingerprint is:
b2:ad:a0:80:85:ad:6c:16:bd:1c:e7:63:4f:a0:00:15 user@host
The key's randomart image is:
+--[ RSA 2048]----+
| E. |
| . |
|. |
|.o. |
|.ooo o. S |
|oo+ * .+ |
|++ +.+... |
|o. ...+. |
| . .. |

For added security '''the key itself''' would be protected using a strong ''passphrase''. If a passphrase is used to protect the key, ssh-agent can be used to cache the passphrase.

2. Copy key to remote host

linuxconfig.local$ ssh-copy-id 
's password:
Now try logging into the machine, with "ssh ''", and check in:


to make sure we haven't added extra keys that you weren't expecting.

3. Login to remote host

Note that no password is required.

linuxconfig.local$ ssh 
Last login: Tue Apr 3 12:47:53 2007 from

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