azure multi model dns failure

[Kevin W Monroe]

I have 2 models in azure, and both have a "machine-X". The last one to come up seems to steal the dns entry.

## repro
juju create-model modelA
juju deploy ubuntu

juju create-model modelB
juju deploy ubuntu

juju switch modelA
juju run --machine 0 'host machine-0'

juju switch modelB
juju run --machine 0 'host machine-0'

## expected results
machine-0 resolves to the private ip address of machine-0 in the current model

## actual results
machine-0 resolves to the private ip address of the most recently deployed machine-0, regardless of model

## more info
http://paste.ubuntu.com/16118291/

This is problematic when you have services that connect to hostnames. In my case, all my big data slaves from modelA try to connect to a master in modelB because the 'machine-X' dns entry points to modelB.

[Andrew Wilkins (axwalk)]

Kevin, this would be because the models were sharing a network previously, which is no longer the case in master/beta-7. I've just bootstrapped master, added a model, and a machine to the second model. "host machine-0" returns a different DNS entry for machine-0 in each model.

[Kevin W Monroe (kwmonroe)]

Awesome Andrew, looks like this was indeed fixed in beta7. I've had lots of models with the same 'machine-x' and each is resolving to its own unique hostname.

Thanks!!