不用密直接用 ssh 登入到端

SSH Without a Password

The following steps can be used to ssh from one system to another without specifying a password.

Notes:The system from which the ssh session is started via the ssh command is the client.The system that the ssh session connects to is the server.These steps seem to work on systems running OpenSSH.The steps assume that a DSA key is being used. To use a RSA key substitute 'rsa' for 'dsa'.The steps assume that you are using a Bourne-like shell (sh, ksh or bash)Some of this information came from:
http://www.der-keiler.de/Mailing-Lists/securityfocus/Secure_Shell/2002-12/0083.html Steps:

On the client run the following commands:

$ mkdir -p $HOME/.ssh$ chmod 0700 $HOME/.ssh$ ssh-keygen -t dsa -f $HOME/.ssh/id_dsa -P ''

This should result in two files, $HOME/.ssh/id_dsa (privatekey) and $HOME/.ssh/id_dsa.pub (public key).

Copy $HOME/.ssh/id_dsa.pub to the server.

On the server run the following commands:

$ cat id_dsa.pub >> $HOME/.ssh/authorized_keys2$ chmod 0600 $HOME/.ssh/authorized_keys2

Depending on the version of OpenSSH the following commandsmay also be required:

$ cat id_dsa.pub >> $HOME/.ssh/authorized_keys$ chmod 0600 $HOME/.ssh/authorized_keys

An alternative is to create a link from authorized_keys2 toauthorized_keys:

$ cd $HOME/.ssh && ln -s authorized_keys2 authorized_keys

On the client test the results by ssh'ing to the server:

$ ssh -i $HOME/.ssh/id_dsa server

(Optional) Add the following $HOME/.ssh/config on the client:

Host server         IdentityFile ~/.ssh/id_dsa

This allows ssh access to the server withouthaving to specify the path to the id_dsa file as an argument to ssheach time.