ssh, аутентификация по ключам
cd ~.ssh; # пусть id_rsa.pub - публичный ключ, alpha - наш сервер cat id_rsa.pub | ssh alpha 'mkdir .ssh; cd .ssh; cat >> authorized_keys2; chmod 600 authorized_keys2' cat id_rsa.pub | ssh alpha 'mkdir .ssh; cd .ssh; cat >> authorized_keys; chmod 600 authorized_keys'