1. The development of cloud computing
Cloud computing is the product of IT technologies as they evolve. To understand cloud computing, we need to be aware of the development of the IT system architecture.
Development of IT system architecture so far can be divided into three stages:
1> physical machine architecture
This stage, deploy and run applications on a physical machine. For example, on a business to ERP system, if small, you can find three physical machines are deployed Web servers, application servers and database servers. If a larger scale, a variety of server cluster architecture can be used, but each cluster member still deployed directly on a physical machine. Early customers are this architecture, a set of application server, usually very low system resource usage, up to 20% are good.
2> virtualization architecture
Determine the physical server computing power is growing, the development of virtualization technology greatly improves the physical server resource utilization. This phase, to run several virtual machines on physical machines, applications deployed directly to a virtual machine. The benefits of virtualization is also reflected in reducing the number of physical machines to manage, while saving maintenance costs.
3> Cloud computing architecture
Virtualization improves the utilization of resources of a single physical machine, with the application virtualization technology, IT environment, there are a growing number of virtual machines, then new demand arises: how IT environment virtual machine unified and efficient management. There is a demand supply, cloud computing boarded the stage of history.
2. Openstack Profile
1> What is cloud computing
Cloud computing is a pay-per-use model, this model offers available, convenient, on-demand network access into a shared pool of configurable computing resources (resource, including networks, servers, storage, applications, services) . Cloud computing public and private cloud points, there are domestic public cloud Ali, Tencent. Jinshan and Huawei. There OpenStack private cloud based on the wave of development, Kyushu, easy Jie Sida, cloud totem, Haiyun Jiexun, Qingyun, etc., based docker, k8s secondary research and development has a soul bird clouds, cloud speed and so on.
2> several levels of cloud computing services included
• SaaS (Software as a Service): The online software as a service.
• Paas (Platform as a Service): the platform as a service.
• Iaas (Infrastructure as a Service): the hardware as a service.
3> OpenStack
By Rackspace and NASA to develop cloud computing platform, it is an open source IaaS (infrastructure and services) cloud computing platform, so anyone can own to build and deliver cloud computing services, semi-annual, written in Python language. OpenStack service Iaas layer.
History 4> OpenStack's
OpenStack name begins with the English alphabetical order of
Merino leather sport: https://baike.baidu.com/item/GNU .
5> OpenStack community
Community: www.openstack.org, wiki.openstack.org
mailing list:
http://wiki.openstack.org/MailingLists#General_List
http://wiki.openstack.org/MailingLists#Development_List
http://wiki.openstack.org/MailingLists#Operators
How to contribute code: http://wiki.openstack.org/HowToContribute
Source code management: http://wiki.openstack.org/GerritWorkflow
Documentation: http://docs.openstack.org beginner hall
3. OpenStack architecture and benefits
OpenStack provides a flexible and scalable private cloud and public cloud computing services, such services must be simple cloud deployment and scalability.
1> loosely coupled modules;
2> assembly configuration is more flexible;
3> secondary development easier.
4. OpenStack constituent components
OpenStack shared service components:
Database Services (Database Service): MairaDB and MongoDB;
Message transmission (Message Queues): RabbitMQ;
Cache (cache): Memcached;
time (time sync): NTP
Memory (storge provider): ceph, GFS, LVM, ISICI the like;
High availability and load balancing: pacemaker, HAproxy, keepalive, lvs etc;
OpenStack core components:
Identity Services (Identity Service): Keystone;
Calculated (Compute): Nova;
Mirroring service (Image Service): Glance;
Network & Address Management (Network): Neutron;
Object Store (Object Storage): Swift;
A storage block (Block Storage): Cinder;
UI interface (Dashboard): Horizon;
Measurement (Metering): Ceilometer;
Deployment schedule (Orchestration): Heat.
5. NTP time synchronization service
Details Reference: https://www.cnblogs.com/ajunyu/p/10883120.html .