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parts of Beginner’s Guide to OpenStack to read before this ~
[Part.2 Basics of Nova] Beginner’s Guide to OpenStack
It’s the main fabric controller for IaaS providing Cloud Computing Service by OpenStack. Took its first baby steps in NASA. Contributed to OpenSource and became most important component of OpenStack.
It built of multiple components performing…..
Nova stores states of virtual machines in a central database. It’s optimal for…..
# API Style
Interface is mostly RESTful. Routes (python re-implementation of Rails route system) packagesmaps URIs to…..
# Threading Model
Uses Green Thread implementation by design using eventlet and greenlet libraries. This results into single process thread for O.S. with it’s blocking I/O issues. Though…..
# Filtering Scheduler
In short it’s the mechanism used by ‘nova-scheduler’ to choose the worthy nova-compute host for new required virtual machine to be spawned upon. It prepare…..
# Message Queue Usage
Nova components use RPC to communicate each other via Message Broker using PubSub. Nova implements rpc.call (request/response, API acts as consumer) and rpc.cast (one way, API acts as publisher)…..
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