Algo parecido com isso dará a você 5 ips flutuantes para escolher, aumente seq
se precisar de mais
neutron net-create --router:external=True --shared ext-net
neutron subnet-create --name ext-subnet --gateway 10.0.3.1 --allocation-pool start=10.0.3.200,end=10.0.3.254 --disable-dhcp ext-net 10.0.3.0/24
# create vm network
neutron net-create ubuntu-net
# if no router subnet pre-exists, we nat 10.0.4.x network here
neutron subnet-create --name ubuntu-subnet --gateway 10.0.4.1 --dns-nameserver 10.0.3.1 ubuntu-net 10.0.4.0/24
neutron router-create ubuntu-router
neutron router-interface-add ubuntu-router ubuntu-subnet
neutron router-gateway-set ubuntu-router ext-net
# create pool of floating ips
i=0
while [ $i -ne 5 ]; do
neutron floatingip-create ext-net
i=$((i + 1))
done