The following process flow takes place when a new virtual machine is launched on OpenStack from the web user interface:
- When the user performs a login by entering his credentials via the Horizon dashboard, the UI invokes Keystone REST APIs for authentication. Keystone performs the authentication and returns back a token. This token is preserved by Keystone in its database and is used for authentication of further REST API requests.
- The user then clicks the Launch Instance button on the dashboard which invokes a nova-api request.
- The request is received by nova-api and is sent to Keystone for validation and access permissions.
- Keystone validates the token and sends an acknowledgment, ...