ssh-keygen -t dsa and follow the prompts. If you're going to use the shared key to log into a system where user identities shouldn't be shared (i.e iVEC) save the key file as something like /home/observer/.ssh/id_dsa_username_galaxy, and use a non-blank passphrasescp .ssh/id_dsa_username_galaxy username@galaxy.org:.ssh/authorized_keys file with a command like cat id_dsa_username_galaxy » .ssh/authorized_keysssh-agent bash and ssh-add .ssh/id_dsa_username_galaxy. You'll have to enter your passphrase once this way.