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

sudo service xxxx stop

sudo service xxxx start

where xxxx is the name of a running service

http://docs.openstack.org/trunk/insta... should have most of the services you need to stop and start listed in the sections around the installation of each piece.

here's a hack you can use to restart one subsystem:

#!/bin/bash

srv=$1
if [ $# -eq 2 ]
then
    action=$2
else
    action=restart
fi
echo usage action $action
cd /etc/init/; for i in $(ls $srv-* | cut -d \. -f 1 | xargs); do sudo service $i $action; done

and invoke with e.g. 'nova' or 'neutron' or 'cinder' etc.