root@ip:/var/lib/juju/tools# rm machine-0
root@ip:/var/lib/juju/tools# ln -s /var/lib/juju/tools/1.22.0-trusty-amd64 machine-0
root@ip:/var/lib/juju/tools# service jujud-machine-0 restart



(/var/lib/juju/tools/1.22.0-trusty-amd64) i get a random tools, or latest