manage port deletion is not validated properly

[Ivar Lazzaro]

When a port belonging to a port pair is deleted, the user sees the following:

neutron port-delete port1
Request Failed: internal server error while processing your request.

This is caused by the DBReferenceError which prevents the used port from being deleted. For better usability, we should catch the event (via neutron registry) and raise a BadRequest error instead.

[Cong Phuoc Hoang (hoangphuoc)]

I think networking-sfc should provide the way to delete port even it belongs to port-pair-group.

[Ivar Lazzaro (mmaleckk)]

That would break the consistency of the port pair. At the very least, if we need to prevent port deletion, it should return a proper BadRequest error to the user instead of an Internal Error

[Cong Phuoc Hoang (hoangphuoc)]

Hi Ivar,

I have a use case about that. If we apply networking-sfc to a group of servers, when scaling-in, server will be terminate. But because of server belongs to a port-pair, so scaling-in does not work normally.

I want to delete a port from a port-pair, then update port-pair-group later, so it will resolve the above issue.