The compute service is composed of multiple components that take care of receiving the request, and launching and managing the virtual machines. Here is a summary of the various building blocks of the compute service:
- The nova-api service interacts with the user API calls that manage the compute instances. It communicates with the other components of the compute service over the message bus.
- The nova-scheduler is the service that listens to the new instance request on the message bus. The job of this service is to select the best compute node for the new instance.
- The nova-compute service is the process responsible for starting and terminating the virtual machines. This service runs on the compute nodes and listens for new requests over the message bus.
The compute nodes are not provided direct access to the database. This design limits the risk of a compromised compute node providing...