Creating SSH Keys for rsync or ssh etc.
Create keys on local machine
ssh-keygen -t dsa
Copy Public Key (id_dsa.pub) to PC you want to log into
scp ~/.ssh/id_dsa.pub username@host:
On the PC you want to log into go to the .ssh folder in the home dir and add the key in to the authorised keys file
cat id_dsa.pub >> authorized_keys
Thats it. The pub key can be deleted off the server. Job Done.
Original = http://www.redbrick.dcu.ie/help/tutorials/ssh_keys/