Revision as of 18:54, 6 December 2012

Overview

Scheduler/Device Management is a separate Quantum plugin. It is responsible for:

• Management of devices that implement advanced services (load balancers, firewalls, vpn gateways, etc). That includes REST API for CRUD operations on device database.
• Binding of service's logical models to devices (ex: schedule vip to load balancer)
• Deployment of configs to devices with help of agent/drivers

Workflow

Example 1. The typical workflow for vip creation:

call sequence.png

Details:

• The request to create pool is is received by LBaaS Plugin
• LBaaS Plugin calls DB plugin to create model and store it to DB, pool_id is returned
• LBaaS Plugin responds to API with "HTTP 202 Accepted". The rest of process is done asynchronously
• LBaaS Plugin calls Scheduler and passes it service_type, pool_id, pool and other optional parameters.
• Scheduler finds device that satisfies service_type and parameters, including those specified in pool.
• Scheduler stores mapping between device_id and pool_id in its DB. This mapping will be used in latter requests
• Scheduler returns device_info to LBaaS plugin
• LBaaS plugin sends rpc message to Agent, specifying command, service_type, logical object (pool) and physical object (device parameters)
• Agent reads message and forwards it to driver
• Driver is responsible to wire device to tenant network according to service insertion mode and deploy logical object to the device
• Agent returns result to LBaaS plugin which updates state of corresponding DB object.

Important note: Agent is common for all services. It delegates processing to drivers[service_type][device_type][version].

See also Scheduler API

Whole component diagram:

diagramm.png