juju bootstrap --debug
09:26:08 INFO  juju.cmd supercommand.go:63 running juju [2.1.0 gc go1.6.2]
09:26:08 DEBUG juju.cmd supercommand.go:64   args: []string{"juju", "bootstrap", "--debug"}
Clouds
aws
aws-china
aws-gov
azure
azure-china
cloudsigma
google
joyent
localhost
rackspace

Select a cloud [localhost]: 

09:26:10 ERROR cmd supercommand.go:458 cloud localhost not found
09:26:10 DEBUG cmd supercommand.go:459 (error details: [{github.com/juju/juju/cmd/juju/commands/bootstrap.go:358: } {github.com/juju/juju/cmd/juju/commands/bootstrap.go:1008: } {github.com/juju/juju/cloud/clouds.go:213: cloud localhost not found}])