You can login to a remote Linux server without entering password using ssky-keygen and ssh-copy-id as explained in this example.
ssh-keygen creates the public and private keys. ssh-copy-id copies the local-host’s public key to the remote-host’s authorized_keys file. sshcopy-id also assigns proper permission to the remote-host’s home, ~/.ssh, and ~/.ssh/authorized_keys.
Step 1: Create public and private keys using ssh-key-gen on local-host
Generating public/private rsa key pair.
Enter file in which to save the key
Enter passphrase (empty for no passphrase): [Press enter key]
Enter same passphrase again: [Pess enter key]
Your identification has been saved in
Your public key has been saved in
The key fingerprint is:
Step 2: Copy the public key to remote-host using sshcopy-id
sathish@local-host$ ssh-copy-id -i ~/.ssh/id_rsa.pub remote-host
Now try logging into the machine, with “ssh ‘remotehost’”,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
Step 3: Login to remote-host without entering the password
sathish@local-host$ ssh remote-host
Last login: Sun May 16 17:22:33 2013 from 192.168.31.1