Comment 0 for bug 1310460

In my testbed, ceilometer throws an exception which is caused wrong key format of neutron:

2014-04-01 10:52:39.135 6104 ERROR notification [-] Insert msg to Mongodb occured error:Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/ceilometer/billing/backend.py", line 74, in insert_data
    self.db[collection].insert(data, safe=True)
  File "/usr/lib64/python2.6/site-packages/pymongo/collection.py", line 357, in insert
    continue_on_error, self.__uuid_subtype), safe)
InvalidDocument: key 'router.interface' must not contain '.'

It seems that mongodb doesn't support "." in key.

A simple and straightforward workaround is to change "." with "_" in l3_db.py.