Failed to detect a valid IP address from -1

Question

I have following the docs 3 times on three different machines and get the same error every time. I'm using https://maas.io/get-started and it's pretty simple--really feel like I cannot be messing this up. So either no one uses this software or I'm missing something completely.

When I get to step 5:

1. There is no Network tab as shown in the docs
2. Clicking on "Subnets" or "Nodes" you get the following error message

The error in the regiond.log is

2017-01-17 17:28:22 maasserver.websockets.protocol: [critical] Error on request (17) subnet.list: failed to detect a valid IP address from -1
Traceback (most recent call last):
  File "/usr/lib/python3.5/threading.py", line 862, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib/python3/dist-packages/provisioningserver/utils/twisted.py", line 824, in worker
    return target()
  File "/usr/lib/python3/dist-packages/twisted/_threads/_threadworker.py", line 46, in work
    task()
  File "/usr/lib/python3/dist-packages/twisted/_threads/_team.py", line 190, in doWork
    task()
--- <exception caught here> ---
  File "/usr/lib/python3/dist-packages/twisted/python/threadpool.py", line 246, in inContext
    result = inContext.theWork()
  File "/usr/lib/python3/dist-packages/twisted/python/threadpool.py", line 262, in <lambda>
    inContext.theWork = lambda: context.call(ctx, func, *args, **kw)
  File "/usr/lib/python3/dist-packages/twisted/python/context.py", line 118, in callWithContext
    return self.currentContext().callWithContext(ctx, func, *args, **kw)
  File "/usr/lib/python3/dist-packages/twisted/python/context.py", line 81, in callWithContext
    return func(*args,**kw)
  File "/usr/lib/python3/dist-packages/provisioningserver/utils/twisted.py", line 857, in callInContext
    return func(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/provisioningserver/utils/twisted.py", line 225, in wrapper
    result = func(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/maasserver/utils/orm.py", line 603, in call_within_transaction
    return func_outside_txn(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/maasserver/utils/orm.py", line 422, in retrier
    return func(*args, **kwargs)
  File "/usr/lib/python3.5/contextlib.py", line 30, in inner
    return func(*args, **kwds)
  File "/usr/lib/python3/dist-packages/maasserver/websockets/base.py", line 358, in list
    for obj in objs
  File "/usr/lib/python3/dist-packages/maasserver/websockets/base.py", line 358, in <listcomp>
    for obj in objs
  File "/usr/lib/python3/dist-packages/maasserver/websockets/base.py", line 205, in full_dehydrate
    return self.dehydrate(obj, data, for_list=for_list)
  File "/usr/lib/python3/dist-packages/maasserver/websockets/handlers/subnet.py", line 62, in dehydrate
    metadata = IPRangeStatistics(full_range)
  File "/usr/lib/python3/dist-packages/provisioningserver/utils/network.py", line 254, in __init__
    self.suggested_gateway = self.get_recommended_gateway()
  File "/usr/lib/python3/dist-packages/provisioningserver/utils/network.py", line 272, in get_recommended_gateway
    return str(IPAddress(first_address - 1))
  File "/usr/lib/python3/dist-packages/netaddr/ip/__init__.py", line 306, in __init__
    'address from %r' % addr)
netaddr.core.AddrFormatError: failed to detect a valid IP address from -1

The server (all three I've tried) obviously has an IP, I can browse to the web interface.

Thoughts?