Openstack is a stack of feature rich cloud computing technologies. Within a short period of its launch Openstack has attained a significant status in the field of cloud computing. Openstack have series of technical projects to leverage the growth of various parts of cloud infrastructure. Even though Openstack was found by Rackspace and NASA, global open source community have a large contribution to the present Openstack which is massively scalable and have a stack of standard cloud technologies. Openstack falls under Apache.2.0 licence, that means it have all the benefits of an opensource product. So you won’t be under the arms of any proprietary vendors and you can extend the code for your business needs. An open source cloud solution that is hardware agnostic like Openstack can save you money, energy and time.
Nova consists of seven main components. The Cloud Controller component will interact with all other components. API Server provides the Web services front end for the cloud controller. Compute Controller provides compute server resources, and the Object Store component provides storage services. Auth Manager provides authentication and authorization services. Volume Controller provides fast and permanent block-level storage for the compute servers. Network Controller provides virtual networks to enable compute servers to interact with each other and with the public network. Scheduler selects the most suitable compute controller to host an instance.
Openstack Object Storage(Swift)
Openstack object storage is openstack software for creating scalable, redundant and reliable storage using standard hardwares. By clustering hardwares, storage can be made to petabyte size. It’s not a file system like storage or realtime data storage but can be used as long term storage for huge static data like virtual images, photo libraries email storage and backup archiving. Swift doesn’t have any central control, it uses a distributed architecture which provides more stability scalability and redundancy.
A storage cluster can be made with Object storage with multiple hardwares. Cluster can be elaborated by adding nodes horizontally or vertically. Data can be written to multiple hardwares, and object storage software ensures the data replication and integrity across the cluster. Object storage can make the data ‘Highly available’ across the node failures. If a node fails object storage will replicate the highly available data stored on other node.
Openstack Image Service (Glance)
The function of glance is to store, retrieve, register and deliver services for virtual images. Glance API server and Glance Registry server are the main components in glance architecture. API server have a standard REST interface for querying details and metadata of the virtual images stored in different types backend storages. The backend stores that Glance can work with are Openstack storage service (Swift), File system, Amazon’s S3 service and HTTP(images that are available via HTTP somewhere on the Internet).With Image service ,users can register new virtual disk images , fetch the details of publicly available virtual disk images and use image library for listing the virtual image disks. Image metadata made available through Glance can be stored in image registries. A registry server is any service that publishes image metadata that belongs to the Glance Registry.
Openstack supports large variety of virtual disks like.
It also has built in management utilities like