Can you provide an example of a case where you are unable to create a port in neutron with a specific IP address?
I do not understand why this is needed with Designate.
If you configure neutron to manage PTR records for ports, Designate will create the required PTR zones based on the IP address. These zones are owned by the project specified in neutron.conf [designate] project_name. These zones will be managed on an octet boundary automatically, based on the ipv4_ptr_zone_prefix_size.
Can you provide an example of a case where you are unable to create a port in neutron with a specific IP address?
I do not understand why this is needed with Designate.
If you configure neutron to manage PTR records for ports, Designate will create the required PTR zones based on the IP address. These zones are owned by the project specified in neutron.conf [designate] project_name. These zones will be managed on an octet boundary automatically, based on the ipv4_ptr_ zone_prefix_ size.