1. The administrator accesses the SC in the WEB mode through the External_api plane, and submits an application for creating a cloud host.
2. The SC accesses the reverse proxy IP address on the LB in the RestAPI mode through the External_api plane, requesting to create a cloud host (SC does not know the existence of the LB).
3. LB selects a Nova-api, accesses Nova-api in the RestAPI mode through the Internal-Base plane, and requests to create a cloud host.
4. After Nova-pai receives the request, he will do the following:
a) authenticate the requester;
b) verify the legitimacy of the message;
c) check the user's quota;
d) generate the task and record the request to the DB through the Internal_base plane;
e) send the message to RabbitMQ in RPC mode through the internal-base plane, requesting nova-conductor to create a virtual machine.
5. After receiving the request, Nova-comductor sends the message to RabbitMQ in the RPC mode through the internal_base plane, requesting nova-scheduler to select a suitable host.
6. After receiving the request, Nova-conductor will select a suitable computing node by means of care, weight and randomness, and return the result to Rabbit-conductor through RabbitMQ through RPC in the internal_base plane.
7. After receiving the result, the Nova-conductor sends the message to the RabbitMQ through the Internal_base plane in the RPC mode, requests the nova-compute of the computing node, and creates a virtual machine.
8. nova_compute will prepare the following resources:
a) applying storage resources to cinder_api in the RPC mode via the Intenal_base plane to the cinder_api;
b) applying network resources to the Neutron-server in the RPC manner via the Intenal_base plane to the Neutron-server;
c) the fc-nova-compute calls the driver to initiate a virtual machine startup request to the VRM through the VRM RestAPI.
