OpenStack Nova 虚拟机创建流程分析

Nova 版本信息

[root@localhost ~]#  nova --version
8.0.0

基于源码分析创建虚拟机流程

+-----------------+
| Dashboard / CLI |
|        |        |
|   nova client   |
+--------|--------+
RESTful API
+--------|--------+
|    nova-api     |
+--------|--------+
RPC CAST
+--------------------|-------------------+
|              nova-conductor            |
|                    |                   |
|                  RPC CALL              |
|   +----------------|---------------+   |
|   |         nova-scheduler         |   |
|   |  host-manager filter hosts     |   |
|   |                |               |   |
|   |  host-manager weigh hosts      |   |
|   |                |               |   |
|   |  random-choice one target host |   |
|   +----------------|---------------+   |
| +------------------|-----------------+ |
| | DB create VM(building + scheduling)| |
| |           DB create RBD            | |
| +------------------|-----------------+ |
+--------------------|-------------------+
PRC CAST
+------------------------|------------------------+
|                   nova-compute                  |
|                        |                        |
|            DB update VM(building + None)        |
|     +------------------|------------------+     |
|     | DB update VM(building + networking) |     |
|     | neutron client: allocate network    |     |
|     +------------------|------------------+     |
| +----------------------|----------------------+ |
| |DB update VM(building + block_device_mapping)| |
| |cinder client:                               | |
| |    create volume from image                 | |
| |    check volume status                      | |
| |    attach volume                            | |
| +----------------------|----------------------+ |
|     +------------------|------------------+     |
|     | DB update VM(building + spawning)   |     |
|     |      compute-driver spawn VM        |     |
|     +------------------|------------------+     |
|                        |                        |
|           DB update VM(active + None)           |
+-------------------------------------------------+