Stopping and starting Nova services - Openstack

When troubleshooting issues with the Compute service you may have a need to stop or start one or all of the Nova services.
So, now that we have configured our OpenStack Compute installation, it’s time to start our services so that they run on both of our OpenStack Compute virtual machines (Controller and Compute), thus making us ready to launch our own private Cloud instances.

How to Learn Stop and Start Nova Services

If you haven’t done so already, ssh to our OpenStack Controller and OpenStack Compute virtual machines. If you created these using Vagrant, you can log in to these using the following commands in separate shells:

Vagrant SSH Controller Vagrant SSH Compute

This assures that we can access our virtual machines, as we will need access to spin up instances from your personal computer.
The OpenStack services that we have been running as a part of our sandbox environments are:

Controller:
nova-api nova-objectstore
nova-scheduler nova-conductor

Compute:
nova-compute nova-network libvirt-bin

Carry out the following steps to stop the OpenStack Compute services we are running:
1. As a part of the package installation, the OpenStack Compute services start-up by default so the first thing to do is to stop them by using the following commands:

(On the Controller node)

sudo stop nova-api
sudo stop nova-scheduler
sudo stop nova-objectstore
sudo stop nova-conductor

(On the Compute node)

sudo stop nova-compute
sudo stop nova-network

Stop the Nova Services

To stop all of the OpenStack Compute services use the following command:

ls /etc/init/nova-* | cut -d ‘/’ -f4 | cut -d ‘.’ -f1 | while read S; do sudo stop $S; done

2. There is also the libvirt service we installed that is stopped in the same way:

sudo stop libvirt-bin

Carry out the following steps to start the OpenStack Compute services:

3. Starting the OpenStack Compute services are done in a similar way as we do to stop them:

(On the Controller node)

sudo start nova-api
sudo start nova-scheduler
sudo start nova-objectstore
sudo start nova-conductor

(On the Compute node)

sudo start nova-compute
sudo start nova-network

To start all of the OpenStack Compute services use the following command:

ls /etc/init/nova-* | cut -d ‘/’ -f4 | cut -d ‘.’ -f1 | while read S; do sudo start $S; done

There is also the libvirt service we installed that is stopped in the same way:

sudo start libvirt-bin

Stopping and starting OpenStack Compute services under Ubuntu are controlled using upstart scripts. This allows us to simply control the running services by the start and stop commands followed by the service we wish to control.