RuntimeError on Bench Start

I’m using bench in development mode, bench start runs successfully but on visiting the site I see the following error:
RuntimeError: no object bound to db with the traceback,


Traceback (most recent call last):
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/middlewares.py", line 15, in __call__
    return super(StaticDataMiddleware, self).__call__(environ, start_response)
  File "/home/oke/Documents/Projects/frappe-bench/env/lib/python2.7/site-packages/werkzeug/wsgi.py", line 766, in __call__
    return self.app(environ, start_response)
  File "/home/oke/Documents/Projects/frappe-bench/env/lib/python2.7/site-packages/werkzeug/wsgi.py", line 766, in __call__
    return self.app(environ, start_response)
  File "/home/oke/Documents/Projects/frappe-bench/env/lib/python2.7/site-packages/werkzeug/local.py", line 228, in application
    return ClosingIterator(app(environ, start_response), self.cleanup)
  File "/home/oke/Documents/Projects/frappe-bench/env/lib/python2.7/site-packages/werkzeug/wrappers.py", line 308, in application
    resp = f(*args[:-2] + (request,))
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/app.py", line 85, in application
    response = frappe.utils.response.handle_session_stopped()
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/utils/response.py", line 183, in handle_session_stopped
    return frappe.website.render.render("message", http_status_code=503)
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/website/render.py", line 28, in render
    path = resolve_path(path.strip('/ '))
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/website/render.py", line 207, in resolve_path
    path = resolve_from_map(path)
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/website/render.py", line 213, in resolve_from_map
    for r in get_website_rules()])
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/website/render.py", line 238, in get_website_rules
    return frappe.cache().get_value('website_route_rules', _get)
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/utils/redis_wrapper.py", line 72, in get_value
    val = generator()
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/website/render.py", line 232, in _get
    for d in frappe.get_all('DocType', 'name, route', dict(has_web_view=1)):
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/__init__.py", line 1177, in get_all
    return get_list(doctype, *args, **kwargs)
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/__init__.py", line 1150, in get_list
    return frappe.model.db_query.DatabaseQuery(doctype).execute(None, *args, **kwargs)
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/model/db_query.py", line 88, in execute
    result = self.build_and_run()
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/model/db_query.py", line 100, in build_and_run
    args = self.prepare_args()
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/model/db_query.py", line 118, in prepare_args
    self.set_optional_columns()
  File "/home/oke/Documents/Projects/frappe-bench/apps/frappe/frappe/model/db_query.py", line 267, in set_optional_columns
    columns = frappe.db.get_table_columns(self.doctype)
  File "/home/oke/Documents/Projects/frappe-bench/env/lib/python2.7/site-packages/werkzeug/local.py", line 347, in __getattr__
    return getattr(self._get_current_object(), name)
  File "/home/oke/Documents/Projects/frappe-bench/env/lib/python2.7/site-packages/werkzeug/local.py", line 310, in _get_current_object
    raise RuntimeError('no object bound to %s' % self.__name__)
RuntimeError: no object bound to db

Environment:
erpnext 10.1.71
frappe 10.1.61
bench 4.1.0
Ubuntu 16.04

Please, how do I resolve this?

hey @Oke can you confirm that mariadb is up and running? We can debug the issue further from there.