Comment by dbaxps for Restart Compute services: # service openstack-nova-api restart # service openstack-nova-cert restart # service openstack-nova-consoleauth restart # service openstack-nova-scheduler restart # service openstack-nova-conductor restart # service openstack-nova-novncproxy restart Restart Networking services. # service neutron-server restart # service neutron-dhcp-agent restart # service neutron-l3-agent restart # service neutron-metadata-agent restart Also restart your chosen Networking plug-in agent, for example, Open vSwitch. # service neutron-openvswitch-agent restart Cinder Services restart # service openstack-cinder-api restart # service openstack-cinder-backup restart # service openstack-cinder-scheduler restart # service openstack-cinder-volume restart On ubuntu run # service --status-all | grep nova # service --status-all | grep neutron To get service names specific to OS

What is going to happen if you shutdown yours devstack created instance and then try to bring it up ? Or just reboot the OS ? How expect your nova process to restart ? Due to what ?