RabitTracker instance has no attribute 'port'

[slowbull]

It always fails when I run the demo tracker/dmlc_local.py -n 2 -s 1 bin/linear.dmlc learn/linear/guide/demo.conf

And I find out that it can't find an available port from 9091 to 9999. So self.port is not defined.

Traceback (most recent call last):
File "tracker/dmlc_local.py", line 100, in
pscmd= (' '.join(args.command) + ' ' + ' '.join(unknown)))
File "/home/jonny/workspace/wormhole/repo/dmlc-core/tracker/tracker.py", line 380, in submit
rabit = RabitTracker(hostIP = hostIP, nslave = nworker)
File "/home/jonny/workspace/wormhole/repo/dmlc-core/tracker/tracker.py", line 142, in init
logging.info('start listen on %s:%d' % (hostIP, self.port))
AttributeError: RabitTracker instance has no attribute 'port'