`ember serve`: Livereload port finding and binding is not atomic

[paddor]

Starting two ember serve processes (e.g. to test a high availability setup) using a Procfile and Hivemind/Overmind (they're like Foreman), one of them usually fails like this:

Livereload failed on http://localhost:49153.  It is either in use or you do not have permission.

Relevant lines from the Procfile:

ember-primary: cd webui && ember serve --port 4200
ember-backup: cd webui && ember serve --port 4201

Running one of them with a prepended sleep 10; often helps, but not always. Maybe you could make that section atomic where Ember tries to find an available port and bind to it?

[btecu]

Probably belongs in https://github.com/ember-cli/ember-cli

[rwjblue]

Agreed, @paddor would you mind moving the issue over to ember-cli's repo?

[paddor]

Sure, just did. Thanks anyway!