How can I re-use a previously assigned floating ip in openstack neutron using horizon?

Question

I have assigned a floating ip to an instance and released it. The floating ip is now free.

If I assigned a new floating ip to the same instance but I get the next floating ip in the range. How can I get the old (just released) floating ip instead?

I am using OpenStack 5.0 and would be interested in how to do this via horizon and the CLI.

Answer 1

neutron floatingip-list will show a list of addresses. Copy the id of the floatingip you want to reassign

You need to identify the port that you want this address assigned to.
neutron port-list (match the ip address of the vm in the list provided and copy the id of the port)

neutron floatingip-associate id_of_floatingip id_of_port

Answer 2

Do not allocate new IP If you want to use already allocated IP (which is not used by any instance)

You can select already allocated unassigned IP from drop down. You don't have to press + button and allocate new IP.