origin: `oc cluster up` hangs at "checking for available ports"

Following the instructions at https://www.openshift.com/devpreview/register.html I’m running

oc cluster up --version=v1.3.0-alpha.1

And this is what I get:

-- Checking Docker client ... OK
-- Checking for existing OpenShift container ... OK
-- Checking for openshift/origin:v1.3.0-alpha.1 image ... OK
-- Checking Docker daemon configuration ... OK
-- Checking for available ports ... ^C

until I break it off manually (waited hours at some point, no difference).

Version

oc v1.3.0-alpha.1 kubernetes v1.3.0-alpha.1-331-g0522e63

Steps To Reproduce

1. run oc cluster up --version=v1.3.0-alpha.1

Current Result

-- Checking Docker client ... OK
-- Checking for existing OpenShift container ... OK
-- Checking for openshift/origin:v1.3.0-alpha.1 image ... OK
-- Checking Docker daemon configuration ... OK
-- Checking for available ports ... ^C

Expected Result

More than the current result 😉

Additional Information

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