Comment 0 for bug 1723026

[problem]
Cannot get the device_id when query floatingip directly, users/admin need to query the specific Floating IP address to find the FloatingIP resources, then find the associated port_id, show port, finally get the device_id. Provide a way to get the device_id from floatingip could be very useful for nova to query the instance by Floating IP address in high performance.

[Use cases]
In cloud env, the cloud admin find there is some abnormal traffics from source IP(Floating IP) in the external FW/Router/Network health check tools. Cloud admin need a ability to find the abnormal vnic and the VM owner to notify that the VM may be under virus attack. So the admin need to stop VM or take other rescue way to process it.

Nova cloud query the instance by floatingip with regex matching filtering, this is also very useful for this destination. Nova store these infos into the network_infocache, it is hard to query instance like this.

Proposal
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* Support list/get floatingip show the related ports' device_id
* Adding regex matching support in DB layer using "LIKE" SQL phrase.