Double ip assignment and unwished removal

[sinicis]

Description

Existing service with type LoadBalancer and the example ip 10.10.10.10 assigned. Another service type LoadBalancer is created with the annotation linkyard.ch/existing-floating-ip: 10.10.10.10. The slb controller will then assign the ip address to the newly created service. If the newly created service is deleted, the slb controller will delete the floating ip address on cloudscale even though it's still in use.

Issue Type
Bug

Wished behaviour

If the floating IP address is already in use it shall not be assigned to the newly created service. Instead an error message like floating ip x.x.x.x is already assigned to service namespace/service. As soon as it's available, the ip address is then assigned.

Further notes

Think about a delayed deletion. If a service gets accidentally deleted it would be nice if the floating ip address is not deleted immediately and can be regained within e.g. 15 minutes.