neutron server should quit without a valid mechanism_drivers setting

[Zoltan Arnold Nagy]

I've made a typo while setting up my environment, accidentally writing "mechanism_driver = openvswitch" instead of "mechanism_drivers = openvswitch", which caused neutron to start without any warnings but port binding fails instantly thus cannot boot VMs.

Should we throw an ERROR while starting and quit, or should we throw an ERROR in the port_binding code?

[yong sheng gong (gongysh)]

I think we should just stop the neutron server.

[Romil Gupta (romilg)]

My 2 cents

I don't think its a valid bug , because we are only processing the following flag in ml2_conf.ini for mechanism drivers:
cfg.CONF.ml2.mechanism_drivers in ml2 managers.py

If user has made the typo then neutron will not know about it. Unless and until we made the mechanism_drivers as a mandatory flag.

[Romil Gupta (romilg)]

Since there is no activity from the assigned person. I am assigning to myself and validate it.

[Romil Gupta (romilg)]

I feel its not a medium defect it should be wishlist.

There are so many flags in ml2_conf.ini and in neutron.

If we fix this then we shouldn't avoid other.

And, moreover the flags are well documented and its a users/customer's responsibility to give the correct flags during deployment :)

So I think we need to have a framework which validates the flags in all conf/ini files.

[Romil Gupta (romilg)]

We are reading this config item as:

    cfg.ListOpt('mechanism_drivers',
                default=[],
                help=_("An ordered list of networking mechanism driver "
                       "entry points to be loaded from the "
                       "neutron.ml2.mechanism_drivers namespace.")),

which states by defaults its [] hence neutron-server keeps running.

I don't feel we could do anything in the code to validate the config is correctly spelled or has some typo mistake.

Anyway, It is well documented in OpenStack-manuals what needs to be configured in ml2_conf.ini.

Hence, marking this bug as invalid.