A common and most important OpenStack question for interview, don't miss this one. Each instance has fixed, private, public, or floating IP addresses. Private IPs are for internal communication among instances; public IPs are for communication within the network but outside the cloud. Whenever we launch an instance, an IP address will be assigned automatically, which will remain the same till its termination, even after reboot.   The cloud administrator configures a pool of IP addresses available in OpenStack compute. The number of floating IP addresses we can assign to a project depends on the limit set in the quota.   For managing the floating IP address, we use the OpenStack command.  Command to list details of the floating IP address.  $ openstack floating ip pool list  Command to allocate a floating IP address to a project.  $ openstack floating ip create public  Command to associate an IP address with an instance.  $ openstack server add floating ip INSTANCE_NAME_OR_ID FLOATING_IP_ADDRESS  Command to disassociate a floating IP address from an instance.  $ openstack server remove floating ip INSTANCE_NAME_OR_ID FLOATING_IP_ADDRESS  Removing floating IP address from a project.  $ openstack floating ip delete FLOATING_IP_ADDRESS