SSH login without password

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

1. 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 (private key) and $HOME/.ssh/id_dsa.pub (public key).

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

3. 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 commands may 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 to authorized_keys:

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

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

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