joceravolo@VMint /usr/local/bin $ trytond -c trytond.conf -d Tryton --all
Traceback (most recent call last):
  File "/usr/local/bin/trytond", line 5, in <module>
    pkg_resources.run_script('trytond==3.7.dev0', 'trytond')
  File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 528, in run_script
    self.require(requires)[0].run_script(script_name, ns)
  File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 1394, in run_script
    execfile(script_filename, namespace, namespace)
  File "/usr/local/lib/python2.7/dist-packages/trytond-3.7.dev0-py2.7.egg/EGG-INFO/scripts/trytond", line 80, in <module>
    server.TrytonServer(options).run()
  File "/usr/local/lib/python2.7/dist-packages/trytond-3.7.dev0-py2.7.egg/trytond/server.py", line 84, in run
    with Transaction().start(db_name, 0) as transaction:
  File "/usr/local/lib/python2.7/dist-packages/trytond-3.7.dev0-py2.7.egg/trytond/transaction.py", line 75, in start
    Database = backend.get('Database')
  File "/usr/local/lib/python2.7/dist-packages/trytond-3.7.dev0-py2.7.egg/trytond/backend/__init__.py", line 30, in get
    ep, = pkg_resources.iter_entry_points('trytond.backend', db_type)
ValueError: need more than 0 values to unpack