oVirt Architecture

Overall architecture

The following diagram shows the different components in the oVirt project:

HOST Agent, 计算节点的代理软件, 用于与管理节点engine通讯, 开启虚拟机, 挂载存储, 运行钩子程序等.

Guest Agent, 虚拟机里面安装的agent, http://www.ovirt.org/Ovirt_guest_agent. 

SPICE 客户端, 用于连接虚拟机的控制界面, 例如console. 客户端需要下载响应的管理软件来连接对应的console, 例如windows中spice和vnc需要Remote Viewer. 下载地址 : 

 http://www.ovirt.org/Console_Client_Resources

http://virt-manager.org/download/

These main components are:

1. Engine (ovirt-engine) - manages the oVirt hosts, and allows system administrators to create and deploy new VMs
2. Admin Portal - web based UI application on top of the engine, that sysadmins use to perform advanced actions.
3. User Portal - a simplified web based UI application for simpler management use-cases.
4. REST API - an API which allows applications to perform virtualization actions, which is used by the command line tools and the python SDK
5. CLI/SDK - The command line interface and SDK provide a way to communicate with engine via script actions.
6. Database - Postgres database is used by the engine to provide persistency for the configuration of the ovirt deployment.
7. Host agent (VDSM) - the oVirt engine communicates with VSDM to request VM related actions on the nodes
8. Guest Agent - The guest agent runs inside the VM, and provides information on resource usage to the oVirt engine. Communication is done over a virtualised serial connection. 
9. AD/IPA - directory services. Engine uses them to receive information on users and groups to be used with ovirt's permissions mechanism.
10. DWH (Data Warehouse) - The data warehouse component performs ETL on data extracted from the db using Talend , and inserts it to history DB.
11. Reports Engine - generates reports based on data in history DB, on system resource usage, using Jasper Reports
12. SPICE client - utility which allows users to access the VMs.

The sections below will give a description and architectural aspects for each such component.