SSH with no password

When you wish to login to a remote system through an ssh session without using any password you'll need to produce a key on the local computer and on the remote computer in order to allow password - free entrance.
first you'll need to produce the key in the local computer:
ssh-keygen -t dsa -b 1024 -P ""
press Enter on the questions followed by the command.
the output will be something like:
Your identification has been saved in /home/yourname/.ssh/id_dsa.
Your public key has been saved in /home/yourname/.ssh/id_dsa.pub.
The key fingerprint is:
4f:9e:4c:17:8f:19:37:32:bc:45:4f:2a:a2:8e:1c:15 yourname@your.loacl.machine
The key's randomart image is:
+--[ DSA 1024]----+
|           .o    |
|           .oo.  |
|          . o+   |
|      o    *.+. .|
|       .E . +  . |
|      o  .+.. . .|
|       +o.o. +   |
|       o+E       |
|       o=.       |
+-----------------+

This will produce two files in you .ssh directory: id_dsa and id_dsa.pub

cat id_dsa.pub into ~/.ssh/authorized_keys on the remote system you want to log into.
change mod to 600:
chmod 600 ~/.ssh/authorized_keys

(source of the tip)